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10 Reasons to Overrule the Fourth Amendment Third Party Doctrine

The U.S. Supreme Court will be hearing arguments this week in Carpenter v. United States, which is one of the most important Fourth Amendment cases before the Court.  The case involves whether the Third Party Doctrine will remain viable.  If so, the Fourth Amendment will fade into obsolescence in today’s digital age.

In this post, I provide 10 reasons why the Third Party Doctrine should be overruled.  Before doing so, here’s some background.

Carpenter [6th Circuit case on cert to the Supreme Court] involved the investigation of a string of robberies of Radio Shack.  The FBI obtained cell phone records of the defendants pursuant to the Stored Communications Act (SCA), which requires “specific and articulable facts” to demonstrate that there are “reasonable grounds to believe” that the records are “relevant and material to an ongoing criminal investigation.” 18 U.S.C. § 2703(d).  This standard is far short of what the Fourth Amendment would require, which is a search warrant based upon probable cause.

The Origins of the Third Party Doctrine

Why did the FBI follow the SCA when the Fourth Amendment has a stricter standard?  The reason is that based upon a flawed interpretation, the Fourth Amendment doesn’t apply to records maintained by third parties – an interpretation that has become known as the Third Party Doctrine.

Back in 1967, the Supreme Court began using a new approach to determine whether there was a Fourth Amendment search (the Fourth Amendment only provides protection if there is a search or seizure).  Using Justice Harlan’s concurrence in Katz v. United States, 389 U.S. 347 (1967), the Supreme Court started looking to whether there was a reasonable expectation of privacy to determine whether there is a search.

Katz was supposed to revolutionize the way the Fourth Amendment was to be understood and applied.  Prior to Katz, the Court looked to whether there was a physical trespass, an approach criticized as antiquated and ill-suited to modern technologies such as telephone wiretapping, which didn’t require a physical trespass into the home (wiretapping could occur in the wires outside the home or at the phone company). Katz brought the Fourth Amendment in to the 20th Century.  Then, the Third Party doctrine came along to lock the Fourth Amendment out of the 21st Century.

Smith v. MarylandUnder the third party doctrine, the U.S. Supreme Court has held that that there is no reasonable expectation in privacy for information known or exposed to third parties. In United States v. Miller, 425 U.S. 435 (1976), the Court held that  there is no reasonable expectation of privacy in financial records maintained by one’s bank because “the Fourth Amendment does not prohibit the obtaining of information revealed to a third party and conveyed by him to Government authorities.”  In Smith v. Maryland, 442 U.S. 735 (1979), the Court concluded that there was no reasonable expectation of privacy when the government obtained a list of phone numbers a person dialed from the phone company because people “know that they must convey numerical information to the phone company” and cannot “harbor any general expectation that the numbers they dial will remain secret.”

Recent Supreme Court cases in Jones and Riley suggest that many Justices are increasingly troubled by the implications of modern technology on the Fourth Amendment.  In her concurrence to Jones, for example, Justice Sotomayor issued a blistering critique of the Third Party Doctrine. But will the Court go so far as to abolish the Third Party doctrine?  That is what is up for grabs here.

10 Reasons Why the Third Party Doctrine
Should be Overruled


1. With modern technology, so much of our data is in the hands of third parties.

Digital Person

The implications of the third party doctrine for the Digital Age are enormous.  Today, so much of our data is maintained by third parties.  Countless companies maintain records about us.  We store documents and photos with cloud service providers.  Credit card companies keep detailed records about our purchases.  Our location information is available to telecommunications companies. Our Web surfing activity is in the hands of ISPs.  Merchants such as have records about our purchases of books and movies and other things.   I wonder whether the justices writing in the 1970s had any idea of how profound the implications of the Third Party Doctrine would be in today’s age.

The third party doctrine is one of the main reasons why the 4th Amendment has often not had much relevance when digital data is involved.  Several courts have held that broad government surveillance programs, including some of the NSA’s surveillance programs, escape the reach of 4th Amendment protection due to the third party doctrine.


2. The Third Party Doctrine implicates privacy in the home, especially with smart homes.

Privacy of the Home

The home is a sacred place in Fourth Amendment jurisprudence.  In case after case, the Supreme Court has held that the quintessential protection of the Fourth Amendment is to protect privacy in the home.  The majority opinion in the Kyllo case involving the use of thermal sensors was basically a love letter about the home.

The government no longer needs to enter a person’s home to learn about that person — the books that person is reading, the person’s communications, hobbies, interests, intellectual exploration, and more can all be learned from third party records.

These days, nearly everything a person owns in her home involves a record maintained by a third party.  Indeed, with the rise of the smart home, third parties will have an unprecedented amount of information about life in the home.

Thus, the home can be searched now through third party records, and that means that the Fourth Amendment will increasingly cease to be much of a protection to privacy in the home.


3. The Third Party Doctrine wrongly assumes that third parties will betray people.


The rationale for the third party doctrine comes from a series of cases involving undercover agents and informants. In these cases, the Supreme Court held that when a person tells another person a secret, she assumes the risk of betrayal. This is known as the Assumption of Risk Doctrine.

In the cases adopting the Third Party Doctrine, the Supreme Court falsely suggested that the Third Party Doctrine logically follows from the Assumption of Risk Doctrine.  The faulty logic is that not only can friends betray a person but so can third parties.

But these situations aren’t analogous.  Misplaced trust with friends involves friends voluntarily choosing to reveal one’s secrets.  But in many instances, third parties don’t voluntarily choose to reveal people’s information. They are forced to by the government. In fact, these companies often want to preserve the confidentiality of people’s information.


4. The Third Party Doctrine flunks contract law.

Third Party Doctrine and Contract Law

The Third Party Doctrine rests upon the notion that people lack an expectation of privacy in records maintained by third parties.  However, in many cases, these third parties have made promises to maintain the privacy of this information.  So, the Third Party Doctrine is saying that contracts and promissory estoppel can’t give rise to reasonable expectations.  But this belies contract law, which is premised on the idea that most contracts will be honored and enforced by courts.

Under the Third Party Doctrine, even if the third party promises explicitly in a contract that it will never share personal data with the government without a warrant, such a contract will still be ignored by the Third Party Doctrine.

The Third Party Doctrine flunks contract law.  People can count on contracts and in many cases can count on promises.  It is certainly reasonable to do so.


5. The Third Party Doctrine fails to comprehend the concept of confidentiality.

Confidentiality and the Third Party Doctrine

If your bank or doctor promises you confidentiality, you expect it to keep its promise.  If a bank or doctor or certain other types of parties breach confidentiality, they can be sued under the tort of breach of confidentiality.

It is reasonable to assume that duties of confidentiality that are protected by tort law will be followed.


6. The Third Party Doctrine means that there is no reasonable expectation of privacy in medical records or any patient health information shared with a doctor.

Patient-Physician Confidentiality - HIPAA and the Fourth Amendment

Would the Supreme Court really hold that people lack an expectation of privacy in their medical data because they convey that information to Third Parties (their physicians)? The result would strike many as absurd.  The logic of the Third Party Doctrine leads to this result, which is probably why the Supreme Court has avoided taking a case that would result in this holding.  It would be the kind of case that would lead to a public uproar.

When faced with the logical implications of a doctrine, the Court can choose from two broad approaches: (1) the Court can confront the logical implications of a doctrine and embrace them or rethink the doctrine; or (2) the Court can cower in the corner and hide and avoid taking cases that require confronting these implications.  Often, the Court has chosen the latter approach.

The HIPAA regulations, 45 C.F.R. §164.512(f), provide that a covered entity may disclose health information to a law enforcement official in compliance with a subpoena or court order, as well as an administrative subpoena or demand.

HIPAA’s approach is only valid if the Third Party Doctrine to the Fourth Amendment applies to medical information and permits a breach of medical confidentiality.


7. People have no choice but to share records and data with third parties.

Smart Phone

Part of the rationale in Smith v. Maryland was that people voluntarily provided information to the phone companies.  This rationale was wrong on the day it was conceived, as it is silly to think that people would just forgo using phones.  The notion that people can just choose to forgo using technology is even more of a howler these days when so much of our lives involves using technologies that create records with third parties.


8. The Third Party Doctrine allows the digital equivalent of general warrants.

Constitutional Convention

There are many debates about the original intent behind the Fourth Amendment, but if there’s one consensus point, it is that the Framers hated general warrants.  A general warrant was a tool used by the British government against the colonials to search broadly for any information relevant to a particular offense.  The Framers explicitly wrote into the Fourth Amendment a prohibition on general warrants with the second clause of the Amendment which states that “no Warrants shall issue, but upon probable cause, supported by Oath or affirmation, and particularly describing the place to be searched, and the persons or things to be seized.”

The Framers viewed general warrants as a tool of oppression – as the overreaching of government authority, as a gross abuse of power.  The Framers didn’t just dislike general warrants.  They loathed them.

But with the Third Party Doctrine, the government can use the digital equivalent to a general warrant.  It can sweep up records maintained by third parties en masse.  That’s because there’s no Fourth Amendment protection – nothing is stopping the government from doing so.  This is the constitutional void in which the NSA started gobbling up metadata.

In some cases, Congress has passed laws restricting the feeding frenzy.  In Carpenter, for example, the Stored Communications Act requires a court order to obtain cell phone records, but that court order is a much weaker standard that what the Fourth Amendment would require.  And, there are many areas remain where nothing provides any protection.


9. The Third Party Doctrine threatens First Amendment rights.

First Amendment and Third Party Doctrine

The Third Party Doctrine is a huge threat to First Amendment rights — the freedom to read, believe, engage in political association, consume ideas, and express oneself.  Much of a person’s intellectual exploration and expression these days involves records existing in the hands of third parties.

In the past, people associated in physical locations.  They bought books with cash and read them in their homes.  Today, with more people buying books from Amazon and reading things online, the government can figure out everything a person is reading from third party records.  Various virtual gathering places and communication involves third party records too.

Privacy is essential to the freedom to engage in First Amendment activities.  The Supreme Court has embraced this notion in many cases by protecting privacy in the context of the First Amendment, such as the protection of anonymity of speech or protection against being compelled to reveal one’s political associations.  This form of privacy, which Neil Richards aptly calls “intellectual privacy,” is imperiled greatly by the Third Party Doctrine.


10. The Fourth Amendment will become increasingly obsolete.

Rotary Phone

These days, so many of our records and data are maintained by third parties, and this trend is increasing.  The Fourth Amendment used to be the main safeguard against government power in snooping into people’s lives.  The Fourth Amendment doesn’t prohibit all searches – it merely prohibits “unreasonable searches and seizures.”  The Fourth Amendment ensures that government officials must justify to a neutral party (judges and magistrates) their need to conduct searches.  It imposes judicial oversight and accountability.  It restricts overbroad searches.  The Fourth Amendment strikes a wise balance between the need of law enforcement officials to investigate crime and the profound importance of protecting the privacy of individuals.

This balance is being eviscerated as the Third Party Doctrine turns the Fourth Amendment into a historical relic.  It is time for the Fourth Amendment to be rejuvenated and brought back to the forefront of managing our privacy in today’s digital age.


My Scholarship on the Issue

If you found my thoughts above to be of interest, I have written a number of books and articles about the Fourth Amendment and Third Party Doctrine that elaborate on the above ideas.  Here are a few:

Carpenter v. United States, Cell Phone Location Records, and the Third Party Doctrine

The Supreme Court on Smart Phones: An Interview of Bart Huffman about Law and Technology

The Nothing-to-Hide Argument – My Essay’s 10th Anniversary


• THE DIGITAL PERSON: TECHNOLOGY AND PRIVACY IN THE INFORMATION AGE (NYU Press 2004) (book available as a free download)

• Fourth Amendment Pragmatism, 51 Boston College Law Review 1511 (2010)

• The First Amendment as Criminal Procedure, 84 New York University Law Review 112 (2007)

• Fourth Amendment Codification and Professor Kerr’s Misguided Call for Judicial Deference, 74 Fordham Law Review 747 (2005)

• Reconstructing Electronic Surveillance Law, 72 George Washington Law Review 1264 (2004)

• Digital Dossiers and the Dissipation of Fourth Amendment Privacy, 75 Southern California Law Review 1083 (2002)

* * * *

This post was authored by Professor Daniel J. Solove, who through TeachPrivacy develops computer-based privacy and data security training. He also posts at his blog at LinkedIn, which has more than 1 million followers.

Professor Solove is the organizer, along with Paul Schwartz, of the Privacy + Security Forum (Oct. 4-7, 2017 in Washington, DC), an annual event designed for seasoned professionals. 

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