Why the Fourth Amendment Must Adapt to the Digital Age

By Nate Reynolds '28

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The Fourth Amendment was written to protect people from unreasonable searches and seizures by the government. (1) However, in today’s day and age, the application of the Fourth Amendment is increasingly controversial, especially because of the amount of personal information modern cell phones hold. Today, most cell phones are tracking people’s locations virtually every moment of the day, including what they are purchasing, how they are purchasing it, and how often. (2)

As a result, courts are faced with the dilemma of whether privacy should be protected when the government uses digital technology rather than a physical search. The Supreme Court has begun addressing this issue, but the law has not yet fully adjusted; the court’s decisions indicate that earlier Fourth Amendment decisions do not easily apply to new technology.

Fourth Amendment cases have previously been based on whether a person has a right to expect privacy. As seen in Katz v. United States, the Constitution provides protection to individuals, not particular places. In this case, the Supreme Court ruled that the government violated the Fourth Amendment by wiretapping a public phone booth. Put simply, a person does not lose privacy rights just because the government does not physically enter private property. (3)

The broad privacy protections, such as those seen in Katz v. United States, were later narrowed. Rather than continuing to expand Fourth Amendment protections, future cases began restricting it. As seen in Smith v. Maryland, the Supreme Court established the third-party doctrine, asserting that individuals relinquish their expectation of privacy concerning information shared with third parties, thereby giving individuals less Fourth Amendment protection. (4)

At the time, this ruling may have seemed more reasonable, as information was limited to basic data such as phone numbers or bank records. However, the modern world is now significantly more involved with technology and cellphones. People now must disclose large amounts of personal data to companies; cellular location records are especially intrusive as they reveal every part of a person’s private life. (5) A phone company holding this information should not lessen the protection location records receive under the Fourth Amendment.

With technology continuously evolving, the Supreme Court began to recognize that digital surveillance presents serious concerns due to its intrusiveness. In the case of Kyllo v. United States, the Court ruled that using devices not available to the general public — in this case, thermal imaging — to reveal information about the inside of a house constituted a search under the Fourth Amendment. (6)

This decision was crucial as the Supreme Court acknowledged the risks of giving the government the ability to obtain private information without any physical trespass. This concern became even more apparent in United v. Jones, where the Court held that tracking vehicles with a GPS and monitoring these vehicles without a warrant violated the Fourth Amendment. (7) While the majority opinion in this case focused on physical trespass as reasoning, the concurring opinions focused on broader privacy concerns raised by long-term tracking.

In Riley v. California, the Supreme Court continued emphasizing this idea by holding that police needed a warrant to search a cell phone obtained during an arrest. (8) This case pinpoints how a cell phone is fundamentally different from any other physical item, as it can hold considerable private and personal information. All in all, these decisions altogether support the broader argument that digital surveillance is more revealing and constitutionally significant than older forms of search, and they prove why the Fourth Amendment should be interpreted with today’s technology in mind.

The Supreme Court’s most important modern digital privacy case is arguably Carpenter v. United States. Within this case, the government obtained historical “transactional records” from a wireless carrier without a warrant. (9) The Court held that the government's warrantless acquisition of Carpenter’s cell-site records violated his Fourth Amendment right; this case was fundamental as the Supreme Court did not apply the third-party doctrine automatically. (10)

Even though the records were held by a phone company, the Court recognized that the location data obtained gave the government access to inordinate amounts of information about Carpenter’s private life. A person does not choose to expose every moment of their life simply by carrying their cellphone. This case aids in demonstrating this notion, warning us against relying too heavily on antiquated legal rules that were created prior to the centralization of digital life.

Overall, these cases highlight that the Fourth Amendment must continue adapting as technology evolves. Previous rules were developed before cell phones could reveal a great deal about a person’s personal and private life. Modern surveillance can be equally, if not more, invasive than a physical search. Because of this, courts must continue interpreting the Fourth Amendment in a manner that recognizes how much of our private lives are not stored on digital devices.

Endnotes

1. United States Courts, “What Does the Fourth Amendment Mean?”

2. NPR, “Why Your Cellphone Could Be Called a ‘Tracker.’”

3. Katz v. United States, 389 U.S. 347 (1967).

4. Bastarrika Soto, “What to Know about the Fourth Amendment’s Third-Party Doctrine.”; Smith v. Maryland, 442 U.S. 735 (1979).

5. Smith v. Maryland, 442 U.S. 735 (1979).

6. Kyllo v. United States, 533 U.S. 27 (2001).

7. United States v. Jones, 565 U.S. 400 (2012).

8. Riley v. California, 573 U.S. 373 (2014).

9. Carpenter v. United States, 585 U.S. 296 (2018).

10. Ibid.