The Fourth Amendment Third-Party Doctrine
Richard M. Thompson II
Legislative Attorney
June 5, 2014
Congressional Research Service
7-5700
www.crs.gov
R43586
The Fourth Amendment Third-Party Doctrine
Congressional Research Service
Summary
In the 1970s, the Supreme Court handed down Smith v. Maryland and United States v. Miller, two
of the most important Fourth Amendment decisions of the 20
th
century. In these cases, the Court
held that people are not entitled to an expectation of privacy in information they voluntarily
provide to third parties. This legal proposition, known as the third-party doctrine, permits the
government access to, as a matter of Fourth Amendment law, a vast amount of information about
individuals, such as the websites they visit; who they have emailed; the phone numbers they dial;
and their utility, banking, and education records, just to name a few. Questions have been raised
whether this doctrine is still viable in light of the major technological and social changes over the
past several decades.
Before there were emails, instant messaging, and other forms of electronic communication, it was
much easier for the courts to determine if a government investigation constituted a Fourth
Amendment “search.” If the police intruded on your person, house, papers, or effects—tangible
property interests listed in the text of the Fourth Amendment—that act was considered a search,
which had to be “reasonable” under the circumstances. However, with the advent of intangible
forms of communication, like the telephone or the Internet, it became much more difficult for
judges to determine when certain surveillance practices intruded upon Fourth Amendment rights.
With Katz v. United States, the Court supposedly remedied this by declaring that the Fourth
Amendment protects not only a person’s tangible things, but additionally, his right to privacy.
Katz, however, left unprotected anything a person knowingly exposes to the public. This idea
would form the basis of Smith and Miller. In those cases, the Court held that a customer has no
reasonable expectation of privacy in the phone numbers he dials (Smith) and in checks and
deposit slips he gives to his bank (Miller), as he has exposed them to another and assumed the
risk they could be handed over to the government.
While the third-party doctrine has been criticized by Members of Congress, various
commentators, and others as overly constrictive of Americans’ privacy rights, it appears to fit
relatively well with other Fourth Amendment case law. That being said, advancements in data
collection, automation, and use have some questioning the continued application of this doctrine
in a digital society. Several events have precipitated renewed debates over its continued existence.
First was the Supreme Court’s decision in the GPS tracking case, United States v. Jones, where
two concurring opinions comprising five Justices of the Court called into question various
existing Fourth Amendment theories, including the third-party doctrine, at least with respect to
long-term government monitoring and advanced surveillance technology. Second was the Edward
Snowden leaks relating to the National Security Agency’s telephone metadata program, which has
been primarily justified by Smith and the third-party doctrine. Various Members of Congress have
joined the debate, with some introducing legislation that would require a warrant for access to
records held by third-parties, and others introducing more targeted measures that would limit
access to information such as geolocation data from third-party companies.
With these legal, social, and technological trends in mind, this report explores the third party-
doctrine, including its historical background, its legal and practical underpinnings, and its present
and potential future applications. It explores the major third-party doctrine cases and fits them
within the larger Fourth Amendment framework. It surveys the various doctrinal and practical
arguments for and against its continued application. Lastly, this report describes congressional
efforts to supplement legal protection for access to third-party records, as well as suggesting
possible future directions in the law.
The Fourth Amendment Third-Party Doctrine
Congressional Research Service
Contents
Introduction ...................................................................................................................................... 1
Fourth Amendment Background ...................................................................................................... 3
Early Definitions of a Fourth Amendment “Search” ................................................................. 5
Reasonable Expectation of Privacy and the Secrecy Model of Privacy .................................... 6
Third-Party Doctrine Jurisprudence ................................................................................................. 7
Undercover Informant Cases ..................................................................................................... 7
Miller v. United States—Subpoena for Bank Records............................................................... 9
Smith v. Maryland—Subpoena for Telephone Call Records ................................................... 11
Other Applications of the Third-Party Doctrine ...................................................................... 12
Support for the Third-Party Doctrine ............................................................................................. 15
Criticism of the Third-Party Doctrine ............................................................................................ 17
Implications of United States v. Jones on the Third-Party Doctrine .............................................. 20
Congressional Response to the Third-Party Doctrine .................................................................... 23
Conclusion ..................................................................................................................................... 25
Contacts
Author Contact Information........................................................................................................... 26
The Fourth Amendment Third-Party Doctrine
Congressional Research Service 1
Introduction
In 1967, the Supreme Court pronounced in Katz v. United States that “[w]hat a person knowingly
exposes to the public, even in his own home or office, is not a subject of Fourth Amendment
protection.”
1
This rule “that a person has no legitimate expectation of privacy in information he
voluntarily turns over to third parties” is known as the “third-party doctrine.”
2
While its reach in
the pre-digital age was relatively limited, the third-party doctrine has provided the government a
powerful investigative tool in a society where people share ever-increasing amounts of
information with others. Many have debated whether these technological and social changes
require the courts to reconsider this doctrine, or, alternatively, whether Congress should step in
and create some form of statutory protection for this information.
3
Over the years, the Court has applied the third-party doctrine to two main sets of cases. In one,
the Court has held that people do not have a reasonable expectation that a person with whom they
are communicating will not later reveal that conversation to the police.
4
In the second, the Court
extended this doctrine to hold that people are not entitled to Fourth Amendment safeguards for
records given to a third-party or data generated as part of a person’s business transactions with a
third-party. In two of the most prominent third-party cases, Smith v. Maryland and United States v.
Miller, the Court held that government access to telephone calling records and bank records,
respectively, were not Fourth Amendment searches for which warrants were required.
5
To be clear, the third-party doctrine does not cover all conceivable information that is transferred
through a third party. For instance, the content of a voice or email communication does not fall
within its scope.
6
The courts have reasoned that the service provider is merely the conduit or
intermediary of those communications and not the recipient; thus, the user does not lose privacy
protection in those communications. On the other hand, both non-content and content information
that is shared directly with a service provider is covered by the third-party doctrine (e.g., the
deposit slips or checks shared with a bank and data kept by the bank relating to transactions with
it). Additionally, non-content information derived from private interactions with others is subject
to the third-party doctrine. This covers data such as telephone numbers dialed, email addresses of
those emailed, or websites visited.
1
Katz v. United States, 389 U.S. 347, 351 (1967).
2
Smith v. Maryland, 442 U.S. 735, 743-44 (1979).
3
See, e.g., Orin Kerr and Greg Nojeim, The Data Question: Should the Third-Party Records Doctrine Be Revisited?,
ABA
J
OURNAL
(Aug. 1, 2012), available at http://www.abajournal.com/magazine/article/
the_data_question_should_the_third-party_records_doctrine_be_revisited/; Orin Kerr, The Case for the Third Party
Doctrine, 107 M
ICH
.
L.
R
EV
. 561, 575 (2009); Richard A. Epstein, Privacy and the Third Hand: Lessons from the
Common Law of Reasonable Expectations, 24 B
ERKELEY
T
ECH
.
L.
J. 1199 (2009); Erin Murphy, The Case Against the
Case for Third-Party Doctrine: A Response to Epstein and Kerr, 24 B
ERKELEY
T
ECH
.
L.
J. 1239 (2009); Stewart Baker,
Smith v. Maryland as a Good First-Order Estimate of Reasonable Privacy Expectations, V
OLOKH
C
ONSPIRACY
(May 4,
2014), available at http://www.washingtonpost.com/news/volokh-conspiracy/wp/2014/05/04/smith-v-maryland-as-a-
good-first-order-estimate-of-reasonable-privacy-expectations/.
4
See infra notes 49-66, and accompanying cases.
5
United States v. Miller, 425 U.S. 435 (1976); Smith, 442 U.S. 735.
6
Katz, 389 U.S. at 352 (voice); United States v. Warshak, 631 F.3d 266, 288 (6
th
Cir. 2010) (email).
The Fourth Amendment Third-Party Doctrine
Congressional Research Service 2
The third-party doctrine has been heavily criticized for unnecessarily constricting Americans’
privacy rights.
7
But whatever one thinks of the rule that citizens are not entitled to Fourth
Amendment protection when they share information with one another, the third-party doctrine is
largely entrenched in other areas of Fourth Amendment case law. For example, it is not a Fourth
Amendment search for the police to dig through one’s trash left on the curb,
8
to track a person’s
movements on public streets,
9
and even to surveil a person in a fenced-in backyard with an
aircraft.
10
In each of these instances, the Court reasoned that because the person exposed his
activities to the public gaze he was no longer entitled to an expectation of privacy.
In addition to the legal attacks on the third-party doctrine, some have questioned its practical
implications in a society which shares almost every facet of its life with various entities.
11
Both
Smith and Miller, decided in the mid- to late-1970s, came before the mass digital revolution
experienced over the last several decades. Since these decisions, there has been a wave of
advancement in data generation, collection, automation, and processing.
12
Whether these new
technologies and shifts in social interaction require courts or lawmakers to revise this review is
currently under debate.
Two major events in the past few years typify this ongoing debate. The first is the conversation
prompted by several concurrences in the 2012 GPS tracking case United States v. Jones.
13
In two
concurring opinions in that case, five Justices opined that warrantless, pervasive government
location monitoring can violate the Fourth Amendment.
14
Commentators have speculated that
these five votes could have significant consequences for other similar ubiquitous surveillance
techniques.
15
And at least one member of the Court, Justice Sotomayor, believes that the third-
7
See, e.g., United States v. Miller, 425 U.S. 435, 447 (Brennan, J., dissenting); Stephen E. Henderson, The Timely
Demise of the Fourth Amendment Third Party Doctrine, 96 I
OWA
L.
R
EV
.
B
ULL
. 396 (2011); C
HRISTOPHER
S
LOBOGIN
,
P
RIVACY AT
R
ISK
:
T
HE
N
EW
G
OVERNMENT
S
URVEILLANCE AND THE
F
OURTH
A
MENDMENT
140 (2007).
8
California v. Greenwood, 486 U.S. 35, 43-44 (1988).
9
United States v. Knotts, 460 U.S. 276, 285 (1983).
10
Florida v. Riley, 488 U.S. 445, 451-52 (1989).
11
See D
ANIEL
J.
S
OLOVE
,
T
HE
D
IGITAL
P
ERSON
:
T
ECHNOLOGY AND
P
RIVACY IN THE
I
NFORMATION
A
GE
202 (2004) (“The
government’s harvesting of information from the extensive dossiers being assembled with modern computer
technology poses one of the most significant threats to privacy of our time.”).
12
Omer Tene and Jules Polonetsky, Big Data for All: Privacy and User Controls in the Age of Analytics, 11 N
W
.
J.
T
ECH
.
&
I
NTELL
.
P
ROP
. 239, *1(2013) (“Big data is upon us.” https://a.next.westlaw.com/Document/
I535f4a8bb78611e28578f7ccc38dcbee/View/FullText.html?navigationPath=
Search%2Fv3%2Fsearch%2Fresults%2Fnavigation%2Fi0ad6040300000146014bbf3f6cbb1298%3FNav%3DANALY
TICAL%26fragmentIdentifier%3DI535f4a8bb78611e28578f7ccc38dcbee%26startIndex%3D1%26contextData%3D%
2528sc.Search%2529%26transitionType%3DSearchItem&listSource=Search&listPageSource=
4f65f444bd87ab8451abbca5a750d542&list=ANALYTICAL&rank=10&grading=na&sessionScopeId=
bbd4e55d34300e25e857bc0ccd7bbb05&originationContext=Search%20Result&transitionType=SearchItem&
contextData=%28sc.Search%29 - co_footnote_F3388167494 Over the past few years, the volume of data collected and
stored by business and government organizations has exploded. The trend is driven by reduced costs of storing
information and moving it around in conjunction with increased capacity to instantly analyze heaps of
unstructured data using modern experimental methods, observational and longitudinal studies, and large scale
simulations. Data are generated from online transactions, email, video, images, clickstream, logs, search queries, health
records, and social networking interactions; gleaned from increasingly pervasive sensors deployed in infrastructure
such as communications networks, electric grids, global positioning satellites, roads and bridges, as well as in homes,
clothing, and mobile phones.”).
13
United States v. Jones, 132 S. Ct. 945 (2012).
14
Id. at 954 (Sotomayor, J., concurring); Id. at 957 (Alito, J., concurring).
15
See, e.g., Priscilla J. Smith, Much Ado About Mosaics: How Original Principles Apply to Evolving Technology in
(continued...)
The Fourth Amendment Third-Party Doctrine
Congressional Research Service 3
party doctrine should be seriously rethought as a whole. The second is the litigation surrounding
the National Security Agency’s telephone metadata program. Several federal courts, including the
Foreign Intelligence Surveillance Court, have applied Smith and the third-party doctrine to uphold
this comprehensive data collection program.
16
One district court judge, however, found Smith
outdated and the NSA program too invasive for Smith to still control this legal question.
17
With these shifts in technology and legal thinking in mind, this report explores the history and
legal foundations of the third-party doctrine. It will first provide background to the Fourth
Amendment and describe in what instances government investigations trigger its protections. It
will then analyze the Court’s third-party doctrine cases and provide doctrinal and practical
arguments for and against its application. Next, this report will examine how Congress has
responded to the third-party doctrine and whether United States v. Jones and subsequent cases
might alter its future application. Lastly, this report will consider any potential future
developments in this fast-moving area of law.
Fourth Amendment Background
Before the advent of modern communications, government officials could not simply subpoena
an Internet Service Provider (ISP), or Amazon, or Google for information relating to a target of
investigation, but had to enter the suspect’s home or office, sometimes by force, to retrieve
personal information directly themselves.
18
During the 18
th
century, British and colonial officials
conducted searches and seizures of people’s homes with little to no suspicion of wrongdoing
pursuant to either a general warrant, which was used mainly in England, or a writ of assistance,
which was used in the American colonies.
19
These indiscriminate government intrusions
contributed to the people’s fear of unrestrained government power and led to the eventual passage
of the Fourth Amendment.
Take, for instance, the formative English search and seizure case Entick v. Carrington, where the
government was investigating John Entick and others for alleged publication of seditious
articles.
20
In that case, government officials broke into Entick’s home with “force and arms,”
(...continued)
United States v. Jones, 14 N.C.
J.L.
&
T
ECH
557, 571 (2013); David Gray & Danielle Keats Citron, A Shattered
Looking Glass: The Pitfalls and Potential of the Mosaic Theory of Fourth Amendment Privacy, 14 N.C. J. L. & Tech.
381 (2013).
16
ACLU v. Clapper, 959 F. Supp. 2d 724 (S.D.N.Y. 2013); Smith v. Obama, No. 2:13-CV-257 (D. Idaho June 3,
2014); In re Application of the Fed. Bureau of Investigation for an Order Requiring the Production of Tangible Things
from [Redacted], No. BR 13-109 (FISA Ct. 2013), available at http://www.uscourts.gov/uscourts/courts/fisc/br13-09-
primary-order.pdf.
17
Klayman v. Obama, 957 F. Supp. 2d 1, 36 (D.D.C. 2013).
18
Thomas K. Clancy, What is a “Search” Within the Meaning of the Fourth Amendment, 70 A
LB
.
L.
R
EV
.
1, 4 (2006)
(“The abhorred English and colonial search and seizure practices involved physical invasions of people’s property.
That was not surprising given that physical invasions were the only way authorities could intrude at the time and given
the lack of technology and other sophisticated surveillance techniques.”); see generally W
ILLIAM
J.
C
UDDIHY
,
T
HE
F
OURTH
A
MENDMENT
:
O
RIGINS AND
M
EANING
602-1791 (2009).
19
See Thomas K. Clancy, The Role of Individualized Suspicion in Assessing the Reasonableness of Searches and
Seizures, 25 U.
M
EM
.
L.
R
EV
. 483, 501-512 (1995) (discussing early English and American search and seizure case
law).
20
Entick v. Carrington, 95 Eng. Rep. 807, 807 (C.P. 1765).
The Fourth Amendment Third-Party Doctrine
Congressional Research Service 4
pried open the locks on his doors, broke open his chests and drawers, and searched his private
papers and books for four hours.
21
The officers conducted this search under the guise of a general
warrant, a legal order which states with a high level of generality the places and things to be
searched and seized. In outlawing these practices, Lord Camden of the English bench observed:
[O]ur law holds the property of every man so sacred, that no man can set his foot upon his
neighbour’s close without his leave; if he does he is a trespasser, though he does no damage
at all; if he will tread upon his neighbour’s ground, he must justify it by law.
22
These same intrusive practices also faced disfavor in the American colonies. British officials
often resorted to writs of assistance, a form of general warrant, which permitted house-to-house
searches.
23
These legal orders generally failed to allege any illegal activity and were not signed
off on by a judge.
24
In the famous Paxton’s Case, leading Boston attorney James Otis attacked
these writs as “the worst instrument of arbitrary power, the most destructive of English liberty,
and the fundamental principles of the constitution, that was ever found in an English law book.”
25
John Adams later commented that these indiscriminate intrusions were “the spark in which
originated the American Revolution.”
26
To prevent the newly established federal government from committing these incursions into their
lives, the American people ratified the Fourth Amendment as part of the Bill of Rights in 1791. It
reads:
The right of the people to be secure in their persons, houses, papers, and effects, against
unreasonable searches and seizures, shall not be violated, and no Warrants shall issue, but
upon probable cause, supported by Oath of affirmation, and particularly describing the place
to be searched, and the person or things to be seized.
27
Over the years, the federal courts have struggled to reconcile the first clause of the Amendment,
which requires that all searches and seizures be reasonable, with the second clause, which
requires that all warrants meet certain minimum requirements such as particularly describing the
place to be searched and the things to be seized.
28
In any event, the Court must first determine
whether the Fourth Amendment’s restrictions apply at all. This is done by asking whether the
government has conducted a “search,” a legal term of art that cannot be resolved by mere
dictionary definition, but instead requires application of the Supreme Court’s intricate, and at
times contradictory, Fourth Amendment case law.
21
Id.
22
Id. at 817.
23
Cuddihy, supra note 18, at 380.
24
Id.
25
Brief of James Otis, M
ASSACHUSETTS
S
PY
, Apr. 29, 1773, at 3.
26
1 J
OHN
A
DAMS
&
C
HARLES
F
RANCIS
A
DAMS
,
T
HE
W
ORKS OF
J
OHN
A
DAMS
:
S
ECOND
P
RESIDENT OF THE
U
NITED
S
TATES
57 (1856).
27
U.S.
C
ONST
. amend. IV.
28
See Scott E. Sundby, A Return to Fourth Amendment Basics: Undoing the Mischief of Camara and Terry, 72 M
INN
.
L.
R
EV
. 383, 383-84 (1988).
The Fourth Amendment Third-Party Doctrine
Congressional Research Service 5
Early Definitions of a Fourth Amendment “Search”
Although the Fourth Amendment was ratified in 1791, the Supreme Court’s first in-depth
interpretation of what constitutes a Fourth Amendment search did not arise until the 1886 case
United States v. Boyd.
29
In Boyd, the government obtained a court order for the Boyds to provide
an invoice of goods they imported which the government planned to use against them in court.
The Boyds produced the invoice, but protested that its production constituted an unreasonable
search and seizure under the Fourth Amendment. Looking to Entick and other pre-Revolutionary
cases for guidance, the Court found that the production of private papers was so similar to an
actual invasion into one’s home that it constituted a Fourth Amendment search.
30
Although Boyd instructed that the Fourth Amendment should be “liberally construed,”
31
the Court
narrowed the scope of what constitutes a search in Olmstead v. United States.
32
In that case,
federal agents investigating the bootlegging activities of a criminal syndicate placed a wiretap on
several phone lines running from the homes and office of four suspects. At no point did the
officers trespass upon the defendants’ property to conduct the tap. The Court held that these
wiretaps should not be considered a search as the “Amendment itself shows that the search is to
be of material things—the person, house, papers, and effects,” and the intangible voice of the
defendants was not covered by its literal terms. The Court further found that the agents did not
engage in “an actual physical invasion” of Olmstead’s home for purposes of conducting the
wiretap.
33
Dissenting in Olmstead, Justice Brandeis observed that in the past, most notably in
Boyd, the Court “refused to place an unduly literal construction” upon the Fourth Amendment.
34
Instead, he continued:
The protection guaranteed by the amendment[] is much broader in scope. The makers of our
Constitution ... sought to protect Americans in their beliefs, their thoughts, their emotions
and their sensations. They conferred, as against the government, the right to be let alone-the
most comprehensive of rights and the right most valued by civilized men. To protect, that
right, every unjustifiable intrusion by the government upon the privacy of the individual,
whatever the means employed, must be deemed a violation of the Fourth Amendment.
35
Nonetheless, in the ensuing years, the Court assessed whether there was a search based on
whether a physical trespass occurred. For instance, it was not considered a search when police
engaged in eavesdropping absent a trespass.
36
However, where the police trespassed upon the
suspect’s property—even by an inch—the Court held that the Fourth Amendment applied.
37
Forty
years later the Court would expressly overrule Olmstead’s literal, trespass-based interpretation of
the Fourth Amendment for a privacy-based test.
29
United States v. Boyd, 116 U.S. 616 (1886).
30
Id.
31
Id.
32
Olmstead v. United States, 277 U.S. 438 (1928).
33
Id. at 466.
34
Id. at 476 (Brandeis, J, dissenting).
35
Id. at 478 (Brandeis, J, dissenting).
36
Goldman v. United States, 316 U.S. 129, 135 (1942).
37
Silverman v. United States, 365 U.S. 505, 511-12 (1961).
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Reasonable Expectation of Privacy and the Secrecy Model of
Privacy
In 1967, the Court decided Katz v. United States, which abandoned the literal interpretation of the
Fourth Amendment—one that protected only persons, houses, papers, and effects—to one that
also protected intangible interests such as privacy.
38
However, while the Court sought to expand
what the Fourth Amendment protects, certain passages in Katz simultaneously foreclosed
protection for anything a person exposes to the public or another person. This would have
significant consequences for government access to records and other information held by third
parties.
In Katz, the FBI was investigating the illegal gambling activities of Mr. Katz. The FBI had
attached an electronic eavesdropping device to the outside of the telephone booth in which Katz
made calls and offered evidence of these calls against Katz at his prosecution. Quite sensibly, the
parties framed the question presented in light of Olmstead’s physical trespass theory, the
controlling Fourth Amendment theory of the day. They debated whether a telephone booth was a
“constitutionally protected area” such that attaching the listening device to its outside would
constitute a Fourth Amendment search.
39
The Court, speaking through Justice Stewart, looked
beyond this traditional inquiry into protected areas, and instead declared that the “Fourth
Amendment protects people, not places.”
40
He observed that the “Amendment protects individual
privacy against certain kinds of governmental intrusion,” but also instructed that it “cannot be
translated into a general constitutional ‘right to privacy[.]’” Such a “right to be let alone by other
people” is left largely to protection under state law.
41
In bypassing Olmstead and formulating the
scope of the Fourth Amendment in light of privacy principles, it became necessary for the Court
to lay down a rule to determine which privacy interests would be protected and which would not.
Unfortunately, the majority provided little by way of guidance on the scope of this rule, beyond to
say that what a person “seeks to preserve as private, even in an area accessible to the public, may
be constitutionally protected” and that the use of the electronic eavesdropping device violated
Katz’s privacy, upon which he “justifiably relied.”
42
Concurring, Justice Harlan developed a two-
part framework for answering this question, which would become Katz’s controlling test.
43
Under
Justice Harlan’s formulation, a court first asks whether the person exhibited an actual or
subjective expectation of privacy and second whether society is likely to deem that expectation
reasonable.
44
Beyond its general assertion that the Fourth Amendment protects people, not places, the majority
made an equally far-reaching observation that “[w]hat a person knowingly exposes to the public,
even in his own home or office, is not a subject of Fourth Amendment protection.”
45
This rule
38
Katz v. United States, 389 U.S. 347 (1967).
39
Id. at 349.
40
Id. at 351.
41
Id. at 350.
42
Id. at 351, 353.
43
Id. at 360 (Harlan, J., concurring); see Kyllo v. United States, 533 U.S. 27, 32-33 (2001) (“In assessing when a
search is not a search, we have applied somewhat in reverse the principle first enunciated in Katz v. United States. ... As
Justice Harlan’s oft-quoted concurrence described it, a Fourth Amendment search occurs when the government violates
a subjective expectation of privacy that society recognizes as reasonable.”).
44
Id. at 361 (Harlan, J. concurring).
45
Katz, 389 U.S. at 351-52.
The Fourth Amendment Third-Party Doctrine
Congressional Research Service 7
adopts what can be called the secrecy model of privacy. Under the secrecy model, once a fact is
disclosed to the public in any way, the information is no longer entitled to privacy protection.
46
This secrecy model, along with the assumption of the risk theory discussed below, would form
the underpinnings of the modern third-party doctrine.
Third-Party Doctrine Jurisprudence
The idea that what a person knowingly exposes to the public is not entitled to constitutional
protection was not an invention of the Katz court, but was embedded in Fourth Amendment
jurisprudence for quite some time. In one of the first Fourth Amendment cases, Ex parte Jackson,
the Court held that anything “exposed” on the outside of a parcel of mail is not entitled to Fourth
Amendment protection.
47
Similarly, under what has come to be known as the “plain view”
doctrine, Justice Brandeis noted in the 1927 case United States v. Lee that the use of a searchlight
to view cases of liquor on the deck of a ship was not a Fourth Amendment search.
48
More
prominently, the Court decided a series of cases throughout the 20
th
century holding that people
do not have a reasonable expectation that a person with whom they are conversing will not later
reveal that conversation to the police. The third-party doctrine would later be extended to
documents and transactional data shared with third parties.
Undercover Informant Cases
In a series of five cases throughout the 20
th
century, the Supreme Court assessed the
constitutionality of the use of undercover agents or informants under the Fourth Amendment. In
On Lee v. United States, the government wired an “undercover agent” with a microphone and sent
him into On Lee’s laundromat to engage him in incriminating conversation.
49
An agent of the
Bureau of Narcotics sat outside with a receiving set to hear the conversation. In the course of
these conversations, On Lee made incriminating statements, which the agent later testified to at
On Lee’s trial. On Lee argued that this evidence was obtained in violation of the Fourth
Amendment. In an opinion authored by Justice Jackson, the Court disagreed, noting that On Lee
was “talking confidentially and indiscreetly with one he trusted” and that the agent was let into
his shop “with the consent, if not implied invitation” of On Lee.
50
In a similar case, Lopez v. United States, the defendant attempted to bribe an internal revenue
agent, who during some of these conversations was wearing a recording device.
51
At trial, Lopez
moved to suppress evidence of the wire recordings as fruits of an unlawful search. Relying on the
On Lee decision, the Court rejected this argument on the grounds that the defendant consented to
the agent being in his office and “knew full well” that the statements he made to the agent could
46
Solove, supra note 11, at 8.
47
Ex parte Jackson, 96 U.S. 727, 736 (1877).
48
See United States v. Lee, 274 U.S. 559 (1927); see also United States v. Martin, 806 F.2d 204, 207 (8
th
Cir. 1986)
(“[I]t was inappropriate to subject the agent’s conduct of looking through the window of the truck to Fourth
Amendment scrutiny in the first place. The agent’s mere observation of gun parts left in plain view on the front seat of
the truck did not implicate any Fourth Amendment rights.”).
49
On Lee v. United States, 343 U.S. 747, 748 (1952).
50
Id. at 751-52.
51
Lopez v. United States, 373 U.S. 427, 430 (1963).
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Congressional Research Service 8
be used against him.
52
Further, the Court noted that the listening device was not used to intercept
conversations the agent could not have otherwise heard, but “instead, the device was used only to
obtain the most reliable evidence possible of a conversation in which the Government’s own
agent was a participant and which that agent was fully entitled to disclose.”
53
In Lewis v. United States, the government sent an undercover federal narcotics agent to the
defendant’s home several times to purchase marijuana.
54
Over the defendant’s objections, the
agent was permitted to recount the conversations at trial. Upon review, the Supreme Court held
that the conversations were not protected under the Fourth Amendment as the defendant had
invited the federal agent into his home and that the statements were “willingly” made to the
agent.
55
Finally, in Hoffa v. United States, a government informant relayed to federal law enforcement
agents the many conversations he had with Jimmy Hoffa about Hoffa’s attempt to tamper with a
jury.
56
Because the informant did not enter Hoffa’s hotel room by force, was invited to participate
in the conversations by Hoffa, and was not a “surreptitious eavesdropper,” the Court concluded
that the Fourth Amendment had not been violated.
57
There appear to be two motivating principles underlying these undercover informant cases. In one
sense, the Court was applying Olmstead’s physical invasion test: because the informants had not
trespassed into the defendants’ homes or offices—in the words of pre-Katz case law, their
“constitutionally protected areas”—there could be no constitutional invasion.
58
Rather, in each
instance, the informant was invited onto the premises. For example, in On Lee, the Court
observed that On Lee could not raise the issue of trespass as he had consented, if not invited, the
agent to enter his business. A claim of trespass could only be made if the agent had entered by
force or by show of authority.
59
In another sense, the Court found that voluntarily telling another
person something gave him consent to share that information with another person including the
government.
60
For instance, Hoffa instructed that the Fourth Amendment does not protect “a
wrongdoer’s misplaced belief that a person to whom he voluntarily confides his wrongdoing will
not reveal it.”
61
Note that these cases came before Katz shifted the Fourth Amendment focus from property to
privacy. Whether Katz would disturb this line of cases was a matter of “considerable
52
Id. at 437.
53
Id. at 439.
54
Lewis v. United States, 385 U.S. 206 (1966).
55
Id at 210, 212.
56
Hoffa v. United States, 385 U.S. 293, 296 (1966).
57
Id. at 302.
58
See Lopez, 373 U.S. at 439 (“And the device was not planted by means of an unlawful physical invasion of
petitioner’s premises under circumstances that would violate the Fourth Amendment.”).
59
See On Lee, 343 U.S. at 751-52.
60
Hoffa, 385 U.S. at 302 (“[The government agent] was in the suite by invitation, and every conversation which he
heard was either directed to him or knowingly carried on in his presence.”); Lopez, 373 U.S. at 438 (“The only
evidence obtained consisted of statements made by the [defendant] to the [government agent], statements which [the
defendant] knew full well could be used against him by [the government agent] if he wished.”).
61
Hoffa, 385 U.S. at 302.
The Fourth Amendment Third-Party Doctrine
Congressional Research Service 9
speculation”
62
until the Court decided United States v. White four years later. In White, an
undercover informant wearing a radio transmitter engaged the defendant in several incriminating
conversations, four of which took place at the informant’s house, and several other conversations
took place in the defendant’s home, a restaurant, and in the informant’s car.
63
The court of appeals
in White interpreted Katz as implicitly overruling this line of cases as it was based on a trespass
doctrine that was “squarely discarded” in Katz.
64
The Supreme Court disagreed, however, and
upheld the surreptitious surveillance. The opinion accepted that the trespass rationale could not
survive after Katz, but that the undercover informant cases were also supported by a “second and
independent ground”—that the informant was not an uninvited eavesdropper, but a party to the
conversation who was free to report what he heard to the authorities.
65
For the Court, White had
assumed the risk that information he shared with the informant could be shared with the police.
66
With White, the Court combined several ideas in its Fourth Amendment jurisprudence: first, that
it is unreasonable for people to expect privacy in information they share with another, and second,
that they assume the risk that that information can be handed over to the government.
67
With these
two theories in mind, the Court resolved two major third-party doctrine cases in the 1970s, United
States v. Miller and Smith v. Maryland.
68
These cases would become the cornerstone of the
modern third-party doctrine, and have been heavily relied upon by government officials to access
various types of transactional data without a search warrant.
Miller v. United States—Subpoena for Bank Records
In 1976, the Court took up its first major third-party doctrine case to deal with transactional
documents in Miller v. United States. In that case, agents of the Treasury Department’s Alcohol,
Tobacco, and Firearms Bureau were investigating Mitch Miller for his participation in an illegal
whiskey distillery.
69
The agents subpoenaed the presidents of several banks in which Miller had
an account to produce all records of accounts including savings, checking accounts, and any loans
he may have had. The banks never informed Miller that the subpoenas had been served, but
ordered their employees to comply with the subpoenas. At one bank, an agent was shown
62
See 1 W
AYNE
R.
L
A
F
AVE
,
S
EARCH AND
S
EIZURE
§ 2.2(f) (2004).
63
United States v. White, 401 U.S. 745, 746-47 (1971).
64
United States v. White, 405 F.2d 838 (7
th
Cir. 1969).
65
White, 401 U.S. at 750 (quoting On Lee, 343 U.S. at 753-54) (“It would be a dubious service to the genuine liberties
protected by the Fourth Amendment to make them bedfellows with spurious liberties improvised by farfetched
analogies which would liken eavesdropping on a conversation, with the connivance of one of the parties, to an
unreasonable search or seizure.”)).
66
Id. at 752 (“Inescapably, one contemplating illegal activities must realize that his companions may be reporting to the
police.”). Assumption of the risk is more commonly found in the context of tort law, where a person assumes certain
risks that accompany the activities he is engaged in. See Murphy v. Steeplechase Amusements Co., 250 N.Y. 479
(1929) (Cardozo, J.) (“Volenti non fit injuria. One who takes part in such a sport accepts the dangers that inhere in it so
far as they are obvious and necessary, just as a fencer accepts the risk of a thrust by his antagonist or a spectator at a
ball game the chance of contact with the ball.”).
67
While primarily concerned with the Fifth Amendment right to self-incrimination, Couch v. United States , 409 U.S.
322, 335(1973), observed that “there can be little expectation of privacy where [tax] records are handed to an
accountant, knowing that mandatory disclosure of much of the information therein is required in an income tax
return.”).
68
United States v. Miller, 425 U.S. 435 (1976); Smith v. Maryland, 442 U.S. 735 (1979).
69
Miller, 425 U.S. at 437.
The Fourth Amendment Third-Party Doctrine
Congressional Research Service 10
microfilm of Miller’s account and provided copies of “one deposit slip and one or two checks.”
70
At the other bank, the agent was shown similar records and was given copies of “all checks,
deposit slips, two financial statements, and three monthly statements.”
71
Copies of the checks
were later introduced into evidence at Miller’s trial.
The lower court held that the government had unlawfully circumvented the Fourth Amendment
by first requiring the banks to maintain the customer’s records for a certain period of time and
second by using insufficient legal process to obtain those records from the bank. In a 7-2 ruling,
the Supreme Court reversed and held that subpoenaing the bank records without a warrant did not
violate the Fourth Amendment. The opinion by Justice Powell discarded the first argument by
noting that previous case law held that merely requiring the bank to retain its customers’ records
did not constitute a Fourth Amendment search.
72
That previous case, however, did not resolve
whether a subpoena was sufficient to access those documents.
73
Miller argued that the bank kept
copies of personal records that he gave to the bank for a limited purpose and in which he retained
a reasonable expectation of privacy under Katz. The Court, applying language from Katz, noted
that “[w]hat a person knowingly exposes to the public ... is not a subject of Fourth Amendment
protection.”
74
The Court concluded that banking documents were not “confidential
communications,” but rather negotiable instruments that were required to transact business
between the customer and the bank. All of the documents contained information “voluntarily
conveyed to the banks and exposed to their employees in the ordinary course of business.”
75
As
with the undercover agent cases, once documents were shared with the bank, they could then be
given to the government without requiring a search warrant. Citing to White, Justice Powell
instructed that a bank customer “takes the risk, in revealing his affairs to another, that the
information will be conveyed by that person to the government.”
76
Looking to both this
assumption of the risk theory and the secrecy model, the Court then included the following
sentence which would come to encapsulate the third-party doctrine:
This Court has held repeatedly that the Fourth Amendment does not prohibit the obtaining of
information revealed to a third party and conveyed by him to Government authorities, even if
the information is revealed on the assumption that it will be used only for a limited purpose
and the confidence placed in the third party will not be betrayed.
77
Based on this assertion, Miller could have no reasonable expectation of privacy in the bank
records and thus the introduction of them at his prosecution did not contravene the Fourth
Amendment.
70
Id. at 438.
71
Id.
72
Miller, 425 U.S. at 441 (quoting California Bankers Assn. v. Shultz, 416 U.S. 21, 54 (1974)).
73
See California Bankers Ass’n, 416 U.S. at 54 n.24.
74
Miller, 425 U.S. at 442 (quoting Katz v. United States, 389 U.S. 347, 351 (1967)).
75
Id.
76
Id. at 443.
77
Id. at 443.
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Congressional Research Service 11
Smith v. Maryland—Subpoena for Telephone Call Records
Several years later, the Court took up the second major third-party doctrine case, Smith v.
Maryland,
78
which would have major implications for government collection of transactional
records, especially those held by third-party companies.
In Smith, the police were investigating the robbery of a young woman, who gave the police a
description of her assailant and the vehicle seen near the scene of the crime.
79
The police later
spotted a man matching the victim’s description driving an identical vehicle in her neighborhood,
which they traced back to Michael Smith. Upon police request, the telephone company installed a
pen register at its central office to record the telephone numbers dialed from Smith’s home. The
device was installed without a warrant or court order. Through the pen register, the police learned
that a call was placed from Smith’s home to the victim’s phone, which would eventually connect
Smith to the robbery. At trial, Smith claimed that any evidence obtained from the pen register
violated his Fourth Amendment rights as the police failed to obtain a warrant before installing it.
This motion was denied, Smith was later convicted of robbery, and the appeals court affirmed his
conviction, holding that the installation of the pen register was not a Fourth Amendment search.
80
In line with Justice Harlan’s formulation of the Katz privacy test, the Supreme Court asked the
following questions: first, whether Smith had a subjective expectation of privacy in the numbers
he dialed, and second, whether that expectation was reasonable.
81
As to the former, the Court
“doubt[ed] that people in general entertain any actual expectation of privacy in the numbers they
dial.”
82
The Court assumed that people, in the main, know and understand that they must convey
the dialed numbers to the company to complete the call; that the company has a process of
recording those numbers; and that the company actually does record those numbers for various
business reasons. It deduced this partially from the fact that phone books inform consumers that
the telephone companies “can frequently help in identifying to authorities the origin of
unwelcome and untroublesome calls” and that customers see a list of their calls recorded on their
monthly phone bills.
83
Even if Smith did harbor a subjective expectation of privacy, the Court found that “this
expectation is not ‘one society is prepared to recognize as ‘reasonable.’”
84
Justice Blackmun cited
to Miller, White, Hoffa, and Lopez for the proposition that “a person has no legitimate expectation
of privacy in information that he voluntarily turns over to third parties.”
85
Because Smith
“voluntarily conveyed” the telephone numbers to the company in the process of making the call,
he had “exposed” that information to the company’s equipment in the “ordinary course of
business” and thus could not reasonably expect privacy in that information.
86
Moreover, the Court
78
Smith v. Maryland, 442 U.S. 735 (1979).
79
Id. at 737.
80
Smith v. Maryland, 283 Md. 156, 173 (1978).
81
Smith, 442 U.S. at 740.
82
Id. at 742.
83
Id. at 742-43
84
Id. at 743 (quoting Katz, 389 U.S. at 361).
85
Id. at 743-44.
86
Id. at 744.
The Fourth Amendment Third-Party Doctrine
Congressional Research Service 12
found that Smith “assumed the risk” that the telephone company would reveal to the police the
numbers he dialed.
87
Although Smith was the Court’s last significant pronouncement on the parameters of the third-
party doctrine, the lower federal courts have applied it in various contexts, with a significant
number of these cases dealing with the transfer of electronic information.
Other Applications of the Third-Party Doctrine
After Miller and Smith, the courts have applied the third-party doctrine to a host of various
scenarios including metadata connected to Internet communications, cell phone location
information, and utility billing records, among others. These cases generally divide along a
content/non-content distinction: the content of a communication, such as the body of an email,
does not fall within third-party doctrine, and other Fourth Amendment rules apply. Addressing
information, such as the to/from line in an email, the outside of a letter, or the telephone numbers
dialed, however, are covered by the doctrine. There have been various rationales for this divide,
the most compelling being the difference between the recipient of the information and companies
that act merely as a conduit or intermediary between two people communicating with each other.
The difference in constitutional treatment between the content of a communication and its non-
content addressing information dates at least as far back as the 19
th
century. In the 1877 case Ex
parte Jackson, the Supreme Court held that the content of a mailed letter was protected under the
Fourth Amendment, while the information exposed to the public, such as the address written on
the outside, was not.
88
This dichotomy was further developed in Katz and Smith. In Katz, the
Court protected the content of Mr. Katz’s communication (his voice), noting that a caller is
“surely entitled to assume that the words he utters into the mouthpiece will not be broadcast to the
world.”
89
Non-content information was not before the Court in Katz. On the other hand, Smith left
non-content information, the numbers he dialed, unprotected, as pen registers do not allow law
enforcement to “hear sound” and “[n]either the purport of any communication between the caller
and the recipient of the call, their identities, nor whether the call was even completed is
disclosed[.]”
90
This distinction between content and non-content has also been applied in the lower courts. In
United States v. Warshak, the Sixth Circuit Court of Appeals held that individuals enjoy a
reasonable expectation of privacy in the content of their emails.
91
The panel noted that “email
requires strong protection under the Fourth Amendment; otherwise, the Fourth Amendment would
prove an ineffective guardian of private communication, an essential purpose it has long been
recognized to serve.”
92
Following Smith’s lead, the courts have taken the opposite approach to
non-content or addressing information that accompanies an email or other electronic
87
Id.
88
Ex parte Jackson, 96 U.S. 727, 733 (1877); see also United States v. Jacobsen, 466 U.S. 109, 114 (1984) (“Letters
and other sealed packages are in the general class of effects in which the public at large has a legitimate expectation of
privacy; warrantless searches of such effects are presumptively unreasonable”).
89
Katz v. United States, 389 U.S. 347, 352 (1967).
90
Smith, 442 U.S. at 741 (quoting United States v. New York Tel. Co. 434 U.S. 159, 167 (1977)).
91
United States v. Warshak, 631 F.3d 266, 288 (6
th
Cir. 2010); see also City of Ontario v. Quon, 560 U.S. 746, 757
(2010) (assuming that petitioner had reasonable expectation of privacy in content of emails).
92
Id. at 286.
The Fourth Amendment Third-Party Doctrine
Congressional Research Service 13
communications. In United States v. Forrester, for example, the Ninth Circuit Court of Appeals
held that the to/from addresses of emails, the IP addresses of websites a person visits, and the
total volume of data transmitted to or from a certain account were not subject to Fourth
Amendment protection.
93
The Ninth Circuit found that like the telephone numbers in Smith, email
and Internet users should know that addressing information “is provided to and used by Internet
Service Providers (ISP) for the specific purpose of directing the routing of information.”
94
Moreover, the court noted that although the government can make an “educated guess” about
what was said in a message or viewed on a particular website, this information does not
“necessarily reveal any more about the underlying contents of the communication than do phone
numbers.”
95
Further emphasizing this distinction, while Smith covered the telephone numbers a
person dials to make a call, government access to the numbers dialed after a call has been placed,
known as “post-cut through dialed digits,” is considered a Fourth Amendment search.
96
These
numbers, which might include “bank account numbers, Social Security numbers, prescription
numbers, and the like,” constitute the “contents of communications” and are “the kind of
information that an individual wants and reasonably expects to be kept private.”
97
Another dividing line between protected and unprotected information pertains to the identity of
the service provider in the chain of communication. If the provider is seen as a party to the
transaction and is a recipient of the information, the records are generally considered “business
records” of that company and subject to the third-party doctrine. This rationale is similar to that
applied in the undercover informant cases. Although the information provided to an informant
constitutes the content of the communication, it is not protected because it was spoken directly to
the agent—in other words, the agent was the recipient of that information. Alternatively, where
the company merely acts as a conduit or intermediary and “passively convey[s]” that information
to an end-user, the material is generally not subject to the third-party doctrine.
98
In Warshak, the Sixth Circuit noted that the ISP was acting as an “intermediary that makes email
communication possible.”
99
Just like the post office which acts as an intermediary of a letter, and
the telephone company which acts as an intermediary to the voice content of phone calls, “emails
must pass through an ISP’s server to reach their intended recipient.”
100
And just as the police are
prohibited from accessing communications from the post office or a telephone company without
first obtaining a warrant, the Sixth Circuit held that a warrant should equally be required to access
more modern forms of communications.
101
Distinguishing the bank records case Miller, the court
found that whereas the bank records, checks, and deposit slips in Miller were given directly to the
93
United States v. Forrester, 512 F.3d 500, 510 (9
th
Cir. 2007).
94
Id. at 510.
95
Id.
96
See In Re of Applications of the United States of America for Orders (1) Authorizing the Use of Pen Registers and
Trap and Trace Devices and (2) Authorizing Release of Subscriber Information, 515 F. Supp. 2d 325, 339 (E.D.N.Y.
2007); see also In re Application of the United States of America for an Order Authorizing (1) Installation and Use of a
Pen Register and Trap and Trace Device or Process, (2) Access to Customer Records, and (3) Cell Phone Tracking, 441
F. Supp. 2d 816, (S.D. Tex. 2006) (deciding case on statutory grounds but noting constitutional concern with access to
post-cut-through dialed digits without a warrant based upon probable cause).
97
In re Application for Subscriber Information, 515 F. Supp. 2d at 336.
98
Forrester, 512 F.3d at 510.
99
Warshak, 631 F.3d at 286.
100
Id.
101
Id.
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Congressional Research Service 14
banks to be used in the “ordinary course of business,” the ISP was the “intermediary, not the
intended recipient of the emails.”
102
The court rejected the government’s arguments that the
“ability” and “right” of the ISP to access emails stored on its servers should eliminate any Fourth
Amendment privacy interests, as a similar ability of the telephone operators in Katz to listen in on
conversations carried over their system did not eliminate a user’s reasonable expectation of
privacy.
103
Another prominent example of this conduit versus recipient dichotomy can be found in lower
federal court cases treating cell location data as a business record not subject to Fourth
Amendment protection. In a 2013 Fifth Circuit Court of Appeals case, the government sought
access to two months of historical cell site location data, which provides the location of a cell
phone based on its proximity to the nearest cell tower.
104
Noting this distinction between
intermediary and recipient, the court found that cell site records are “clearly business records” for
which the third-party doctrine should apply, as the cell provider is a party to the transaction; the
location information is not transferred to anyone but the provider; and the location information is
needed to route the call.
105
Like the Fifth Circuit, several lower courts have applied the third-party
doctrine to hold that access to cell site location information is not a Fourth Amendment search.
106
However, over the past several years, a growing number of judges have pushed back against
government attempts to circumvent the Fourth Amendment warrant requirement when seeking
information about an individual’s cell phone location data. The District Court for the Eastern
District of New York, for instance, found that while the third-party doctrine generally covers the
type of location information produced by a cell phone call, the “cumulative” collection of 113
days of constant surveillance implicated sufficiently heightened privacy interests to warrant an
exception to the third-party doctrine.
107
This argument is based on the “mosaic theory” of the
Fourth Amendment, which holds that while short-term monitoring may not reveal anything overly
private about an individual, the aggregation of this information can be much more revealing.
108
In
an alternative approach, the Third Circuit Court of Appeals reasoned that a cell phone user does
not “voluntarily” share his location with a cell phone provider “in any meaningful way,”
prohibiting application of the third-party doctrine, but held that it was left to the discretion of the
magistrate judge whether a warrant would be required.
109
A more recent legal problem facing the lower courts is determining whether the third-party
doctrine should apply to “cell tower dumps.” These are instances in which the government is
looking for the cell phone records of unknown persons who may have made a cell phone call after
102
Id. at 288.
103
Id. (emphasis in original).
104
In re Application of the United States of America for Historical Cell Site Data, 724 F.3d 600, 602 (5
th
Cir. 2013).
105
Id. at 612.
106
See, e.g., In re Application of the United States of America for an Order for Disclosure of Telecommunications
Records and Authorizing the Use of a Pen Register and Trap and Trace, 405 F. Supp. 2d 435, 449-50 (S.D.N.Y. 2005);
United States v. Graham, 846 F. Supp. 2d 384, 403 (D. Mar. 2012); United States v. Benford, No. 2:09-CR-86, 2010
WL 1266507 (N.D. Ind. 2010).
107
In re Application of the United States of America for an Order Authorizing the Release of Historical Cell-Site
Information, 809 F. Supp. 2d 113, 126 (E.D.N.Y. 2011).
108
See infra “Implications of United States v. Jones on the Third-Party Doctrine,” pp. 21-23.
109
See In re Application of the United States of America for an Order Directing a Provider of Electronic
Communication Service to Disclose Records to the Government, 620 F.3d 304, 317-18 (3d 2010).
The Fourth Amendment Third-Party Doctrine
Congressional Research Service 15
a reported crime, say, a bank robbery. The government requests all the calls made from the
nearest cell tower within a certain period of time.
110
The few courts that have addressed the issue
have split on whether a warrant is required.
111
Thus far, the reasoning in these cases has not been
fully developed.
Beyond the specific factors the courts have used to determine whether the third-party doctrine
should apply (e.g., content versus non-content, intermediary versus recipient), there have been
both doctrinal and practical arguments made for and against its very existence.
Support for the Third-Party Doctrine
Perhaps the strongest argument in support of the third-party doctrine is its ability to be
harmonized with the rest of Fourth Amendment case law. One only has to quickly scan the
Supreme Court Reporter to realize that the third-party doctrine is consistent with numerous other
cases which hold that acts or things revealed to the public are not entitled to Fourth Amendment
protection.
Take, for instance, the garbage collection case, California v. Greenwood.
112
There, the police
requested that a trash collector pick up a suspect’s plastic trash bags left in front of his house so
the officer could search it for contraband or other evidence of criminal activity. The Court
concluded that the defendant was not entitled to a reasonable expectation of privacy in his trash as
he discarded it where it could be accessed by the public.
113
Similarly, in United States v. Knotts,
the Court held that a person does not have a legitimate privacy expectation in his public
movements as he voluntarily conveys this information to anyone who wants to look.
114
This
theory has also been applied to cases where police flew an airplane 1,000 feet and a helicopter
400 feet over private property in search of illegal activity.
115
The rationale in those cases was that
any member of the public flying in federally regulated airspace could have looked down and seen
what the officers saw, vitiating any privacy expectation in that space.
116
In United States v.
Jacobsen, the Court held that it was not a search when police opened a mailed package after its
contents had already been viewed by an employee of a private freight carrier.
117
There, the Court
observed that once the defendant’s privacy expectation had been frustrated by one person, it
became public information subject to government investigation.
118
110
See Brian L. Owsley, The Fourth Amendment Implications of the Government’s Use of Cell Tower Dumps in Its
Electronic Surveillance, 16 U.
P
A
.
J.
C
ONST
.
L. 1, 1-2 (2013).
111
Compare In re Application of the United States of America for an Order Pursuant to 18 U.S.C. § 2703(d), 964 F.
Supp. 2d 674, 678 (denying access to cell tower dump records) with United States v. Capito, No. 3:10-CR-8050 (D.
Ariz Sept 14, 2011) (upholding access to cell tower dump records).
112
California v. Greenwood, 486 U.S. 35, 37 (1988).
113
Id. at 42.
114
United States v. Knotts, 460 U.S. 276, 281-82 (1983).
115
California v. Ciraolo, 476 U.S. 207, 213-14 (1986) (airplane); Florida v. Riley, 488 U.S. 445, 455 (1989)
(helicopter).
116
Ciraolo, 476 U.S. at 213-214; Riley, 488 U.S. at 451.
117
United States v. Jacobsen, 466 U.S. 109, 117-18 (1984).
118
Id. at 117. Like the Fourth Amendment, under the privacy tort of intrusion upon seclusion, which subjects one to
liability for intruding upon the solitude or seclusion of another, there is no liability for observing or taking a person’s
photograph in public for his appearance is “open to the public eye.” R
ESTATEMENT
(S
ECOND
)
OF
T
ORTS
§ 652B cmt. b
(continued...)
The Fourth Amendment Third-Party Doctrine
Congressional Research Service 16
As a more practical matter, assistance from third parties is utilized by law enforcement in almost
every investigation. When investigating a murder, robbery, or any other crime committed in the
real world, police officers will usually interview witnesses to obtain facts about the crime. To
conduct these interviews, the officers generally need not obtain a warrant, and witnesses who
refuse to cooperate can be compelled to testify with a grand jury subpoena.
119
It could be argued
that this process of fact finding is very similar to requesting documentary evidence held by third
parties and the same standard should be applied to each.
In this same vein, Professor Orin Kerr has defended the third-party doctrine on the ground that it
maintains the appropriate balance of privacy and security in the face of technological change.
120
Without the ability to use third parties such as telephone or Internet companies, Kerr posits, the
criminal would traditionally have to go out into the public to commit his crime where the Fourth
Amendment offers more limited protection. He argues that a criminal can use the services of
these third parties to commit crimes without having to expose these activities to areas open to
public surveillance.
121
This, he posits, upsets the privacy-security balance that undergirds the
Fourth Amendment because it would require police to have probable cause to obtain any evidence
of the crime: “The effect would be a Catch-22: The police would need probable cause to observe
evidence of the crime, but they would need to observe evidence of the crime first to get probable
cause.”
122
Kerr contends that the third-party doctrine responds to this imbalance by providing the
same amount of protection regardless of whether the defendant commits the crime on his own or
through the use of a third-party service.
From an institutional perspective, one might argue that the courts are not the proper branch of the
federal government to resolve privacy disputes related to information handed over to third-
parties. Once the Supreme Court outlaws, or significantly limits, a certain police practice, it
“constitutionalizes” it, and only the Court or a constitutional amendment could overturn this
decision. Instead, some argue that when creating rules that pertain to new technologies, Congress,
and legislatures generally, might be best fitted to find the appropriate balance between privacy
and security, while providing the necessary flexibility to change this rule as technology
changes.
123
Another argument in support of the third-party doctrine is that the companies which hold a
person’s records “own” them, as they are in possession of them and are generally the ones that
create them.
124
Once possessed by the company, the argument runs, it can transfer these
documents to others free from the permission of the subject of the documents. The Court relied
on this theory in Miller, where it noted that the bank records were not the defendant’s “private
(...continued)
(2013).
119
United States v. Dionisio, 410 U.S. 1, 9-10 (1973) (observing the “historically grounded obligation of every person
to appear and give his evidence before the grand jury. ‘The personal sacrifice involved is a part of the necessary
contribution of the individual to the welfare of the public.’ And while the duty may be ‘onerous’ at times, it is
‘necessary to the administration of justice.’”).
120
See Orin Kerr, The Case for the Third Party Doctrine, 107 M
ICH
.
L.
R
EV
. 561, 575 (2009).
121
Id.
122
Id. at 576.
123
See Orin Kerr, The Fourth Amendment and New Technologies: Constitutional Myths and the Case for Caution, 102
M
ICH
.
L.
R
EV
. 801, 859 (2004).
124
Slobogin, supra note 7, at 157 (describing arguments for and against the possessory interest argument).
The Fourth Amendment Third-Party Doctrine
Congressional Research Service 17
papers,” and as such he could “assert neither ownership nor possession.”
125
Instead, they were
deemed “the business records of the banks.”
126
This argument is buttressed by the theory that the
First Amendment protects a person’s right to communicate facts to others.
127
Criticism of the Third-Party Doctrine
While the third-party doctrine appears to fit reasonably well with the rest of Fourth Amendment
case law, and has other weighty arguments in its favor, it has also had its share of vocal critics
both on and off the Court. There have been four major arguments against its application: (1)
privacy is not an all-or-nothing proposition that is lost once information is disclosed to another
person or company; (2) information sent to third-party companies is not actually “voluntary,” as
people need these services to participate in modern society; (3) the judiciary should not impose
privacy regimes on the citizenry without engaging in a more comprehensive privacy analysis; and
(4) failing to protect information shared with others has the potential to breed distrust among
people or businesses communicating with each other.
The first major argument against the third-party doctrine challenges the notion that once privacy
is lost to one person, it is lost to the world. At bottom, this is a challenge to the secrecy model of
the Fourth Amendment. The secrecy theory of privacy has been criticized for not taking into
consideration that people may not want to engage in “total disclosure” of information they share
with others, but instead seek to selectively disclose that information.
128
Justice Marshall said as
much in dissent in Smith v. Maryland,where he argued that “privacy is not a discrete commodity,
possessed absolutely or not at all.”
129
He continued: “Those who disclose certain facts to a bank
or phone company for a limited business purpose need not assume that this information will be
released to other persons for other purposes.”
130
Several commentators have similarly argued that
there is an important distinction between information that is broadcast to the world and that which
is disclosed in a controlled environment.
131
The first category, they argue, includes instances
where the government accesses information that is readily available in the public square, such as
information posted on a publicly available website or a loud conversation overheard in an
airport.
132
Because the person has decided to release this information to the public, he cannot later
claim to have an expectation of privacy. The latter category, on the other hand, entails a more
limited sharing that is “an integral part of a legitimate transaction” between the individual and the
recipient of the information, and is entitled to Fourth Amendment protection.
133
125
United States v. Miller, 425 U.S. 435, 440-41 (1976)
126
Id.
127
See Eugene Volokh, Freedom of Speech and Information Privacy: The Troubling Implications of a Right to Stop
People from Speaking About You, 52 S
TAN
.
L.
R
EV
. 1049, 1053 (2000).
128
See Kenneth L. Karst, “The Files”: Legal Controls Over the Accuracy and Accessibility of Stored Personal Data,
31 L
AW
&
C
ONTEMP
.
P
ROBS
. 342, 344 (1966).
129
Smith, 442 U.S. at 749 (Marshall, J., dissenting).
130
Id.
131
Susan W. Brenner & Leo L. Clarke, Fourth Amendment for Shared Privacy Rights in Stored Transactional Data, 14
J.L.
&
P
OL
’
Y
211, 258 (2006).
132
Id.
133
Id. This idea that a person loses all Fourth Amendment protection in information he shares with another would seem
to be undermined by various cases in which shared information or spaces did not lose constitutional protection. For
instance, in Minnesota v. Olson, the Court held that an overnight guest could have a reasonable expectation of privacy
(continued...)
The Fourth Amendment Third-Party Doctrine
Congressional Research Service 18
Along these same lines, some have pointed out the apparent inconsistency in Fourth Amendment
protection accorded to various types of information people share with third parties. In Katz v.
United States and Berger v. New York, the Court held that people have an expectation of privacy
in the content of their conversations,
134
while similar protection was not extended to the telephone
numbers dialed in Smith.
135
Dissenting in Smith, Justice Stewart, who authored the Katz majority
opinion, pointed out this incongruity, noting that like telephone numbers, the voice of a
conversation must be transmitted through the telephone company’s equipment and may be
overheard or recorded by that company.
136
He argued that “what the telephone company does or
might do with those numbers is no more relevant to this inquiry than it would be in a case
involving the conversation itself.”
137
Instead, Justice Stewart would have granted both forms of
information protection under Katz.
138
In a line that would foreshadow more recent arguments
against the third-party doctrine, Justice Stewart contended that people are not concerned about
revealing a list of their telephone calls because it could be incriminating, but rather because it
would “reveal the most intimate details of a person’s life.”
139
The second major argument against the third-party doctrine challenges the idea that people
“voluntarily” convey information to others when engaging in business transactions. In Miller, the
Court asserted that the financial statements and deposit slips were “voluntarily conveyed” to the
banks in the “ordinary course of business,”
140
and in Smith the defendant “voluntarily conveyed
numerical information to the telephone company.”
141
More recently, a federal court of appeals
judge made a similar argument regarding cell phone users:
Their use of their phones, moreover, is entirely voluntary. The Government does not require
a member of the public to own or carry a phone. As the days of monopoly phone companies
are past, the Government does not require him to obtain his cell phone service from a
particular service provider that keeps historical cell site records for its subscribers, either.
And it does not require him to make a call, let alone to make a call at a specific location.
142
There has been significant disagreement, however, about how voluntary these transactions really
are. Justice Brennan argued in dissent that “for all practical purposes, the disclosure by
individuals or business firms of their financial affairs to a bank is not entirely volitional, since it is
impossible to participate in the economic life of contemporary society without maintaining a bank
account.”
143
Similarly, Justice Marshall argued in Smith that “unless a person is prepared to forgo
(...continued)
in the home of his host, “a place where he and his possessions will not be disturbed by anyone but his host and those
his host allows inside.”
133
On the other hand, these cases took place in the context of the home, an area accorded the
highest Fourth Amendment protection, and their holdings might not easily extend to other contexts.
134
Katz v. United States, 389 U.S. 347, 353 (1967); Berger v. New York, 388 U.S. 41, 51 (1967).
135
Smith, 442 U.S. at 745.
136
Id, at 746 (Stewart, J., dissenting).
137
Id. at 747 (1979) (Stewart, J., dissenting).
138
Id.
139
Id. at 748 (Stewart, J., dissenting).
140
United States v. Miller, 425 U.S. 435, 442 (1976).
141
Smith, 442 U.S. 442 U.S. 744.
142
In re Application of the United States of America for Historical Cell Site Data, 724 F.3d 600, 613 (5
th
Cir. 2013)
(internal citation omitted),
143
United States v. Miller, 425 U.S. 435, 451 (1973) (Brennan, J., dissenting) (quoting Burrows v. Superior Court, 13
Cal. 3d 238, 247 (1974)).
The Fourth Amendment Third-Party Doctrine
Congressional Research Service 19
use” of the telephone, which for “many has become a personal or professional necessity, he
cannot help but accept the risk of surveillance. It is idle to speak of ‘assuming’ risks in contexts
where, as a practical matter, individuals have no realistic alternative.”
144
One commentator has
argued that unlike the undercover agent cases, where refusing to talk to a particular individual is a
“realistic option,” refusing to get medical treatment or an education would lead to an
“unproductive” and “possibly much foreshortened existence.”
145
The third central argument against the third-party doctrine challenges the assertion that people
“assume the risk” when handing information over to third parties. People do not assume legal
risks as a matter of pure deduction, the argument goes, “but assume only those risks of
unregulated government intrusion that the courts tell us we have to assume.”
146
Dissenting in
White, Justice Harlan expressed concern about the process by which courts determine how much
privacy protection people should expect and will receive. He notes that people’s expectations of
privacy and the risks they assume are “reflections” of the laws handed down by courts or
legislatures. Because it is the “task of the law to form and project, as well as mirror or reflect,”
Justice Harlan instructs, “we should not, as judges, merely recite the expectations and risks
without examining the desirability of saddling them upon society.”
147
Instead of allowing “the
substitution of words for analysis,” courts should assess “the nature of a particular practice and
the likely extent of its impact on the individual’s sense of security balanced against the utility of
the conduct as a technique of law enforcement.”
148
In other words, rather than simply applying
the phrase “assumption of the risk” in each new legal context, Justice Harlan suggested that
courts should look anew at each surveillance practice and determine its actual impact on the
individual’s privacy interests.
149
One commentator has suggested a similar approach in that the
government should not have “practically unrestricted access” to people’s records, or, on the
flipside, that probable cause must be required for every request of documents. Instead, he argues
that the level of protection should depend on the nature of the documents requested.
150
For
example, certain types of records, including public records, may not be entitled to the same
protection as others, such as medical or financial records.
151
144
Smith, 442 U.S. at 750 (Marshall, J., dissenting).
145
Slobogin, supra note 7, at 156.
146
Id. at 157; see also Stephen E. Henderson, The Timely Demise of the Fourth Amendment Third Party Doctrine, 96
I
OWA
L.
R
EV
.
B
ULL
. 39, 47 (“It is the law that defines what risks we do and do not assume.”) .
147
White, 401 U.S. at 786 (Harlan, J., concurring). A similar, and more general, criticism has been posed against the
Katz ‘s reasonable expectation of privacy test. Some have argued that it in determining which expectations of privacy
are reasonable, judges are merely imposing their own views of privacy on society. See United States v. Jones, 132 S.
Ct. 945, 962 (2012) (Alito, J., concurring) (“The Katz expectation-of-privacy test ... is not without its own difficulties.
It involves a degree of circularity, and judges are apt to confuse their own expectations of privacy with those of the
hypothetical reasonable person to which the Katz test looks.”); Minnesota v. Carter, 525 U.S. 83, 97 (1998) (Scalia, J.,
concurring) (“In my view, the only thing the past three decades have established about the Katz test ... is that,
unsurprisingly, those ‘actual (subjective) expectation[s] of privacy’ ‘that society is prepared to recognize as
‘reasonable,’’ bear an uncanny resemblance to those expectations of privacy that this Court considers reasonable.”).
148
United States v. White, 401 U.S. 745, 786 (1971) (Harlan, J., concurring).
149
See Catherine Hancock, Warrants for Wearing a Wire: Fourth Amendment Privacy and Justice Harlan’s Dissent in
United States v. White, 79 M
ISS
.
L.
J. 35 (2009). Similar to Justice Harlan’s comments, the majority in Smith v.
Maryland observed that if people’s subjective expectations of privacy becomes conditioned by government practices
that were “alien to well-recognized Fourth Amendment freedoms,” that a “normative inquiry would be proper” in
determining what constituted a “legitimate expectation of privacy.” Smith, 442 U.S. at 740-41 n.5.
150
Slobogin, supra note 7, at 157.
151
Slobogin, supra note 7, at 157.
The Fourth Amendment Third-Party Doctrine
Congressional Research Service 20
Lastly, many practical arguments have been formulated against application of third-party
doctrine. Justice Harlan believed one of the main concerns with the third-party doctrine was its
ability to breed distrust in people who are communicating with others. He noted that the practice
of third-party bugging “undermine[s] the confidence and sense of security in dealing with one
another that is characteristic of individual relationships between citizens in a free society.”
152
In
Justice Harlan’s view, “words would be measured a good deal more carefully and communication
inhibited if one suspected his conversations were being transmitted and transcribed.”
153
One only
has to look to the recent NSA controversy as a more modern example. Some argue that
knowledge that information shared with tech companies like Google, Facebook, and Apple might
end up in the hands of the government has the potential to engender distrust and cost American
businesses significant revenues both at home and abroad.
154
Implications of United States v. Jones on the Third-
Party Doctrine
In addition to the doctrinal and practical arguments made against the third-party doctrine, several
concurring opinions in the recent GPS tracking case United States v. Jones prompt additional
questions about its continued application. Some argue that these opinions foreshadow a shift in
the Court’s thinking about the effect of technology on the government’s ability to collect large
data sets about American citizens.
In Jones, the police attached a GPS tracking device to the underbelly of Jones’s car and tracked it
24 hours a day for 28 days without a warrant.
155
Under controlling precedent, a person had no
reasonable expectation of privacy when traveling on public streets because he has revealed his
movements to the public at large.
156
While it appeared that Jones required a strict application of
this previous case law, the Court ruled 9-0 against the government, and held that the investigative
activity there constituted a Fourth Amendment search. The reason why, however, was far from
unanimous.
The majority opinion, written by Justice Scalia, and joined by Chief Justice Roberts and Justices
Kennedy, Thomas, and Sotomayor, held that the physical attachment of the tracking device on
Jones’s car, coupled with the intent to obtain information about his movements, amounted to a
Fourth Amendment search.
157
When the police attached the device, they physically trespassed
onto his vehicle, his “effect,” a constitutionally protected area under the Fourth Amendment’s
protection of “persons, houses, papers, and effects.”
158
As Justice Scalia’s opinion relied upon a
152
White, 401 U.S. at 787 (Harlan, J., dissenting).
153
Id.
154
See John Naughton, Edward Snowden’s Not the Story, the Internet Is, T
HE
G
UARDIAN
(July 23, 2013), available at
http://www.theguardian.com/technology/2013/jul/28/edward-snowden-death-of-internet;
Allan Holmes, NSA Spying
Disclosures Could Cost Companies Billions (Sept. 10, 2013), available at http://www.salon.com/2013/09/10/
nsa_spying_disclosures_could_cost_companies_billions_in_sales_newscred/.
155
United States v. Jones, 132 S. Ct. 945, 948 (2012). The D.C. Metropolitan police had obtained a warrant, but it had
expired the day before the device was installed and was installed in the wrong jurisdiction. Id. at n.1.
156
United States v. Knotts, 460 U.S. 276, 281 (1983).
157
Jones, 132 S. Ct. at 949.
158
Id. at 949; U.S.
C
ONST
. amend. IV.
The Fourth Amendment Third-Party Doctrine
Congressional Research Service 21
trespass theory of the Fourth Amendment, it will likely not have major repercussions for the third-
party doctrine, unless one accepts that the government trespasses on an individual’s “papers” or
“effects” when it accesses records from third-party companies.
159
However, two concurring opinions in Jones by Justices Sotomayor and Alito might signal the
willingness of five Justices to reevaluate future applications of the third-party doctrine, at least
with respect to pervasive government monitoring. Justice Sotomayor’s solo concurrence provided
the more far-reaching of the two opinions. She directly called into question “the premise that an
individual has no reasonable expectation of privacy in information voluntarily disclosed to third
parties.”
160
She observed:
This approach is ill suited to the digital age, in which people reveal a great deal of
information about themselves to third parties in the course of carrying out mundane tasks.
People disclose the phone numbers that they dial or text to their cellular providers; the URLs
that they visit and the e-mail addresses with which they correspond to their Internet service
providers; and the books, groceries, and medications they purchase to online retailers.... I for
one doubt that people would accept without complaint the warrantless disclosure to the
Government of a list of every Web site they had visited in the last week, or month, or year.
But whatever the societal expectations, they can attain constitutionally protected status only
if our Fourth Amendment jurisprudence ceases to treat secrecy as a prerequisite for privacy. I
would not assume that all information voluntarily disclosed to some member of the public
for a limited purpose is, for that reason alone, disentitled to Fourth Amendment protection.
161
It seems that Justice Sotomayor, if not prepared to discard the third-party doctrine in whole, is
willing to significantly limit its reach, especially when the government is accessing a wealth of
data about an individual. Again, it should be noted that Justice Sotomayor was the only member
to articulate this more expansive roll-back of the third-party doctrine.
More generally, both Justices Sotomayor and Alito’s opinions could be interpreted to call into
question the continued application of the third-party doctrine insofar as it permits pervasive
government monitoring. In his concurrence, Justice Alito, joined by Justices Ginsburg, Breyer,
and Kagan, found that while short-term monitoring may be permissible under past precedent, “the
use of longer term GPS monitoring in investigations of most offenses impinges on expectations of
privacy.”
162
Justice Sotomayor, who joined the majority but also concurred separately, agreed
159
See Smith, supra note 15, at 571 (“One possibility is that Scalia’s physical trespass analysis applies to digital
trespass. After all, if an agent were to digitally connect with your computer, GPS device, or mobile phone for
investigatory purposes, she is appropriating your property for purposes of gathering evidence, just like the agents who
placed the tracker on your car.”); Jack Wade Nowlin, The Warren Court’s House Built on Sand: From Security in
Persons, Houses, Papers, and Effects to Mere Reasonableness in Fourth Amendment Doctrine, 81 M
ISS
.
L.
J.
1017,
1046-47 (2012) (“On the ‘protected interest’ view, one would retain one’s right to security in the papers against
governmental intrusion. The essence of the traditional security in protected interests, grounded in the law of property, is
the right to exclude—which, of course, includes the right to selectively include some individuals while excluding
others. On this view, one has a right to allow some actors access to one’s home or papers while still excluding others—
such as the police. It would thus invade the core of the protected interest for the government to obtain papers through a
third party and search through them—without the owner’s permission.”).
160
Jones, 132 S. Ct. at 957 (Sotomayor, J., concurring).
161
Id.
162
Jones, 132 S. Ct. at 964 (Alito, J., concurring).
The Fourth Amendment Third-Party Doctrine
Congressional Research Service 22
with Justice Alito’s approach and would have gone even further to find that short-term monitoring
should be prohibited in some instances.
163
These five Justices expressed two interrelated concerns. First, they were uneasy about the
government’s ability to gather, analyze, and use an extensive volume of information about each
person’s comings and goings. Justice Sotomayor observed that “GPS monitoring generates a
precise, comprehensive records of a person’s public movements that reflects a wealth of
information about her familial, political, professional, religious, and sexual associations.”
164
This
idea, commonly referred to as the “mosaic theory,” posits that the aggregation of information
about a person can reveal a whole lot more about him than each part in isolation. The Justices
were not the first to espouse this theory. Before the case reached the Supreme Court, the District
of Columbia Court of Appeals below articulated a similar sentiment in finding that the
government’s month-long location tracking constituted a Fourth Amendment search:
Prolonged surveillance reveals types of information not revealed by short-term surveillance,
such as what a person does repeatedly, what he does not do, and what he does ensemble.
These types of information can each reveal more about a person than does any individual trip
viewed in isolation. Repeated visits to a church, a gym, a bar, or a bookie tell a story not told
by any single visit, as does one’s not visiting any of these places over the course of a month.
The sequence of a person’s movements can reveal still more; a single trip to a gynecologist’s
office tells little about a woman, but that trip followed a few weeks later by a visit to a baby
supply store tells a different story. A person who knows all of another’s travels can deduce
whether he is a weekly church goer, a heavy drinker, a regular at the gym, an unfaithful
husband, an outpatient receiving medical treatment, an associate of particular individuals or
political groups—and not just one such fact about a person, but all such facts.
165
In addition to this aggregation issue, the Justices expressed concern about the ability of
technology to significantly reduce natural barriers such as limited resources and political
accountability that in the past would have limited law enforcement overreach in the field of
surveillance.
166
For Justice Alito, the fact that the government simply could not have tracked a
person’s every movement for a month-long period under traditional law enforcement methods led
him to conclude that the tracking was overly intrusive.
167
While Justice Sotomayor directly criticized the third-party doctrine, one could read Justice Alito’s
concurrence as limited solely to monitoring conducted directly by government agents, and not
extending to instances where third parties collect data on individuals. That being said, the
combination of the Jones concurrences has already had an effect in third-party cases in lower
federal courts. For example, the District Court for the District of Columbia applied a variation of
the mosaic theory to invalidate the NSA’s collection of telephone call records.
168
Citing to the
Jones concurrences, Judge Richard H. Leon acknowledged that the type of information collected
163
Id. at 957 (Sotomayor, J., concurring).
164
Jones, 132 S. Ct. at 955.
165
United States v. Maynard, 615 F.3d 544, 562 (D.C. Cir. 2010).
166
See Jones 132 S. Ct. at 956 (Sotomayor, J., concurring) (“And because GPS monitoring is cheap in comparison to
conventional surveillance techniques and, by design, proceeds surreptitiously, it evades the ordinary checks that
constrain abusive law enforcement practices: ‘limited police resources and community hostility.’”) (quoting Illinois v.
Lidster, 540 U.S. 419, 426 (2004)).
167
Jones, 132 S. Ct. at 964 (Alito, J., concurring).
168
Klayman v. Obama, 957 F. Supp. 2d 1, 36 (D.D.C. 2013).
The Fourth Amendment Third-Party Doctrine
Congressional Research Service 23
under the NSA’s metadata program was very similar to that upheld in Smith, “but the ubiquity of
phones has dramatically altered the quantity of information that is now available and, more
importantly, what that information can tell the Government about people’s lives.”
169
And, as
described above, judges in certain cell phone location monitoring cases have applied Jones and
the mosaic theory to deem months-long government tracking a Fourth Amendment search.
170
In
the long run, it may take a more pertinent set of facts for the Justices to advance the arguments
enunciated in Jones.
Congressional Response to the Third-Party Doctrine
Notwithstanding the concurring opinions in Jones, the bulk of Supreme Court and lower federal
court precedent have left most non-content information unprotected by the Fourth Amendment. In
some instances, Congress filled this void by creating varying levels of privacy protection for this
type of non-content information. However, these protections are in the main not as robust as the
warrant requirement, and in some instances, searches may be justified by little more than “official
curiosity.”
171
Seven years after the Court handed down Smith and ruled that government access to telephone
toll records was not covered by the Fourth Amendment, Congress enacted as part of the
Electronic Communications Privacy Act of 1986 (ECPA) several provisions requiring the
government to seek a court order before using a pen register or trap and trace device.
172
Again,
these devices allow the government to gather dialed telephone numbers and email addressing
information, among other non-content information.
173
Under 18 U.S.C. § 3123, a court “shall
issue an ex parte order authorizing the installation and use of a pen register or trap and trace
device ... if the court finds that the attorney for the Government has certified that the information
likely to be obtained by such installation and use is relevant to an ongoing criminal
investigation.”
174
A few things should be noted about this provision. First, the “shall” language removes discretion
from the judge; if the judge finds the government has made the required certification, he must
issue the order.
175
Second, while the court must ensure that the government has made the proper
certification, ECPA does not require an “independent judicial inquiry into the veracity of the
169
Id. at 35-36.
170
In re Application of the United States of America for an Order Authorizing the Release of Historical Cell-Site
Information, 809 F. Supp. 2d 113, 126 (E.D.N.Y. 2011).
171
See United States v. Morton Salt Co., 338 U.S. 632, 652 (1950) (describing relevancy standard for subpoenas).
172
Electronic Communications Privacy Act of 1986, P.L. 99-508, § 301, 100 Stat 1848.
173
As enacted in 1986, the pen register statute, by its terms, only authorized the interception of telephone metadata. 100
Stat. 1871 (“[T]he term ‘pen register’ means a device which records or decodes electronic or other impulses which
identify the numbers dialed or otherwise transmitted on the telephone line to which such device is attached.”)
(emphasis added). Congress extended the pen register/trap and trace authority to also cover Internet addressing
information as part of the United and Strengthening America by Providing Appropriate Tools Required to Intercept and
Obstruct Terrorism (USA PATRIOT Act) of 2001, P.L. 107-56, §216, 115 Stat. 272, 288, codified at 18 U.S.C. § 3127.
174
18 U.S.C. § 3123.
175
See United States v. Fregoso, 60 F.3d 1314, 1320 (8
th
Cir. 1995) (“The judicial role in approving use of trap and
trace devices is ministerial in nature because, upon a proper application being made under 18 U.S.C. § 3122, ‘the
court shall enter an ex parte order authorizing the installation’ of such a device. 18 U.S.C. § 3123(a)”) (emphasis in
original)).
The Fourth Amendment Third-Party Doctrine
Congressional Research Service 24
attested facts.”
176
This means that the judge will not make an independent assessment whether the
relevancy standard has been met, but only that the government has made the proper certification.
One district court has noted that “the extremely limited judicial review required by [the pen
register statute] is intended merely to safeguard against purely random use of this device.”
177
One
magistrate judge went so far as to describe his role under the pen register statute as a “rubber
stamp” limited to “proofreading errors,” and that “without independent judicial review, the
authorization of pen registers is subject to misuse and abuse.”
178
Third, the relevancy standard,
which again the government, and not the court, determines if it has been met, is a “far from
burdensome” legal standard.
179
The Supreme Court has held, at least in the subpoena context, that
information sought is not relevant only if “there is no reasonable possibility that the category of
materials the Government seeks will produce information relevant to the general subject” of the
investigation.
180
In light of this relatively lax standard, several prominent commentators on
privacy and technology have suggested that Congress should increase the evidentiary threshold
under Section 3123 from mere relevance to at least a reasonable suspicion standard similar to that
used for accessing certain stored communications.
181
Also included in ECPA is the Stored Communications Act (SCA), in which Congress provided
varying degrees of protection to information historically subject to the third-party doctrine and,
thus, outside the reach of the Fourth Amendment. Under 18 U.S.C. § 2703(c), service providers
must hand over “records or other information pertaining to a subscriber” so long as the
government can establish “specific and articulable facts” that the records are “relevant and
material” to an ongoing criminal investigation.
182
This is akin to the Terry reasonable suspicion
standard—it is lower than probable cause but does require the government to articulate its basis to
believe that the information is connected to criminal activity.
183
This standard has been applied to
data such as the to/from address line in an email or the IP addresses of websites a person has
visited. Some courts have construed Section 2703(d) in conjunction with the pen register statute
to allow the government access to cell site location information.
184
Section 2703(c)(2) requires
the providers to hand over other customer information such as their name, address, telephone
calling records, length of service, telephone number, and means and source of payments,
176
In re Application of the United States of America for an Order Authorizing the Installation and Use of a Pen
Register and Trap and Trace Device, 846 F. Supp. 1555, 1559 (M.D. Fla. 1994); see also S. Rpt. 99-541, at 47 (1986)
(“[Section 3123] does not envision an independent judicial review of whether the application meets the relevance
standard, rather the court needs only to review the completeness of the certification submitted.”).
177
United States v. Hallmark, 911 F.2d 399, 402 (10
th
1990).
178
In re Application of the United States of America for an Order Authorizing the Installation and Use of a Pen
Register and Trap and Trace Device, 846 F. Supp. 1555, 1564-65, 1563 n.4 (M.D. Fla. 1994).
179
In Re of Applications of the United States of America for Orders (1) Authorizing the Use of Pen Registers and Trap
and Trace Devices and (2) Authorizing Release of Subscriber Information, 515 F. Supp. 2d 325, 329 (E.D.N.Y. 2007).
180
United States v. R. Enterprises, Inc., 498 U.S. 292, 301 (1991).
181
See Anti-Terrorism Investigations and the Fourth Amendment After September 11, 2001: Hearing Before the
Subcomm. on the Constitution of the H. Comm. of the Judiciary, 108
th
Cong. 21, 26 (2003) (statements of James
Dempsey, Center for Democracy and Technology, and Orin S. Kerr, Law Professor).
182
18 U.S.C. § 2703(d).
183
In re Application of the United States of America for an Order Pursuant to 18 U.S.C. § 2703(d), 707 F.3d 283, 287
(4
th
Cir. 2013).
184
In re Application of the United States of America for an Order for Disclosure of Telecommunications Records and
Authorizing the Use of a Pen Register and Trap and Trace, 405 F. Supp. 2d 435, 449-50 (S.D.N.Y. 2005).
The Fourth Amendment Third-Party Doctrine
Congressional Research Service 25
including credit card or bank account numbers with either an administrative, grand jury, or trial
subpoena.
185
Additionally, Congress has passed more targeted privacy protection laws. For instance, the
privacy of cable subscribers is safeguarded under the Cable Communications Privacy Act of
1984,
186
and the privacy of video store customers under the Video Privacy Protection Act.
187
More recently, various Members of Congress have sought to temper the reach of the third-party
doctrine with respect to transactional data. Several days after the Edward Snowden leaks became
public, Senator Paul filed the “Fourth Amendment Restoration Act of 2013” (S. 1121) in an effort
to “stop the National Security Agency from spying on citizens of the United States[.]”
188
This bill
would require that “[t]he Fourth Amendment to the Constitution shall not be construed to allow
any agency of the United States Government to search the phone records of Americans without a
warrant based upon probable cause.”
189
While dictating to the judiciary what the Fourth
Amendment should and should not protect may be beyond Congress’s constitutional power,
190
Congress clearly can play a role in setting substantive and procedural limitations on government
surveillance authorities. For instance, Senator Paul has introduced a similar bill, the “Fourth
Amendment Preservation and Protection Act of 2013” (S. 1037), which would prohibit federal,
state, and local government officials from accessing information relating to an individual held by
a third party in a “system of records.”
191
Other congressional measures would alter the third-party
doctrine in a more targeted way. Several location monitoring bills would, for instance, prohibit
companies from sharing their customers’ location information unless the government obtained a
warrant or one of several limited exceptions applied.
192
Conclusion
So what does the future have in store for the third-party doctrine and the government’s collection
of non-content, transactional data? At this point, there appears to be only one solid vote on the
Court in Justice Sotomayor for eliminating or significantly reducing the scope of this doctrine.
Although there are hints in Justice Alito’s Jones opinion that he and the three members of his
concurrence are ready to reconsider this rule when it comes to pervasive government surveillance,
his rationale was left somewhat underdeveloped. It will take future opinions to get a better sense
of whether or how far these Justices are willing to go to limit government access to non-content
information held in the hands of third parties. In the meantime, the lower federal courts might
continue to limit or distinguish the third-party doctrine in specific and narrow instances. For
instance, in the NSA telephone metadata case, Judge Leon limited Smith to its facts and held that
185
18 U.S.C. § 2703(c)(2).
186
47 U.S.C. § 551; see Kerr, supra note 123, at 855 (“A broader look at the legal standards that govern criminal
investigations involving new technologies suggests that Congress has often taken the lead, and that judicial decisions
interpreting the Fourth Amendment generally have played a secondary role”).
187
18 U.S.C. § 2710.
188
Fourth Amendment Restoration Act of 2013, S. 1121 (1
st
Sess. 2013).
189
Id.
190
See Dickerson v. United States, 530 U.S. 428, 437 (2000) (“Congress may not legislatively supersede our decisions
interpreting and applying the Constitution.”).
191
Fourth Amendment Preservation and Protection Act of 2013, S. 1037, 113
th
Cong. (1
st
Sess. 2013).
192
See, e.g., Geolocation Privacy and Surveillance Act, S. 639, H.R. 1312, 113th Cong (1st Sess. 2013).
The Fourth Amendment Third-Party Doctrine
Congressional Research Service 26
it did not apply to this more comprehensive data collection program.
193
Likewise, if and when the
Supreme Court is asked to reconsider the scope of the third-party doctrine, it is more likely to
carve out specific exceptions than to overturn it in its entirety. This approach would permit the
courts to engage in a more nuanced, normative approach to analyzing the privacy interests
implicated by accessing records derived from transactions between people and other various
entities.
Another possibility is for Congress to act. Justice Alito observed in Jones that “[i]in
circumstances involving dramatic technological change, the best solution to privacy concerns
may be legislative” as “a legislative body is well situated to gauge changing public attitudes, to
draw detailed lines, and to balance privacy and public safety in a comprehensive way.”
194
This
argument that Congress is best suited to address the nuanced policy questions that privacy and
security entails has been expressed by commentators as well.
195
Like the courts, it appears
unlikely that Congress would be willing to completely eliminate the third-party doctrine. On the
other hand, Congress may be more inclined to engage in a subject-by-subject approach, in which
Congress limits the third-party doctrine in certain areas. Congress provided statutory protection
for telephone toll records in the pen register/trap and trace statute; for Internet metadata in the
Stored Communications Act; and for video customer records in the Video Privacy Protection Act.
It could enact similar protection for other subject areas where non-content information is shared
with companies as a necessary part of doing business.
Author Contact Information
Richard M. Thompson II
Legislative Attorney
rthom[email protected], 7-8449
193
Klayman, 957 F. Supp. 2d at 37 (“[T]he Smith pen register and the ongoing NSA Bulk Telephony Metadata Program
have so many significant distinctions between them that I cannot possibly navigate these uncharted Fourth Amendment
waters using as my North Star a case that predates the rise of cell phones.”).
194
Jones, 132 S. Ct. at 964.
195
Kerr, supra note 123, at 857.
