A proper understanding of the Fourth Amendment can accommodate modern technology, even though that technology was not known at the time.
One of the important issues for originalism is whether it can be applied to new circumstances that were not envisioned at the time of the original Constitution. Perhaps this issue is encountered most often when considering the application of the Fourth Amendment to new technology. In this essay and my next, I explain how these issues can be resolved in theory and as applied to two specific cases: Riley v. California (the search of cell phones when a person is arrested) and Kyllo v U.S. (the use of heat sensors to determine the temperature inside a home—as a means of discovering whether illegal pot is being grown there).
The Fourth Amendment to the Constitution guarantees “the right of the people to be secure in their persons, houses, papers, and effects, against unreasonable searches and seizures.” But difficult issues arise as to how this Amendment, which was written in a horse-and-buggy world, should be applied to cell phones and other modern technology.
Under the modern interpretation of the Fourth Amendment, which does not apply the original meaning, these issues are largely avoided. In the 1967 case of Katz v. United States, the Supreme Court began the development of a nonoriginalist approach to the Amendment. In that case, the government placed a device on the outside of a phone booth which amplified the sound inside, allowing the government to hear the contents of a call. The Court held the use of the device was a search and Justice Harlan’s concurrence provided the test for this approach. Under that test, the government undertakes a Fourth Amendment search whenever it engages in an activity that interferes with the reasonable expectations of privacy of an individual. Because Harlan believed the individual had a reasonable expectation of privacy during his phone conversation inside the enclosed phone booth, the government had undertaken a Fourth Amendment search.
This test has allowed the Court to address modern technology that was not anticipated by the Framers of the Bill of Rights. The Court simply asks whether an individual had a reasonable expectation of privacy. But this advantage of the test has been purchased at a great cost, since the test is largely a blank check for the Court, which can freely determine based on its own beliefs whether an individual had a reasonable expectation of privacy when engaging in some activity.
The Katz reasonable expectations of privacy test is also problematic, because it does not accord with the Fourth Amendment’s original meaning. As the Court’s two strongest originalists—Justices Thomas and Gorsuch—recently said in the case of U.S. v. Carpenter, the test is inconsistent in various ways with the original meaning. Perhaps most importantly, the test asks whether something is a search based on whether there is a reasonable expectation of privacy as to the matter. By contrast, the Fourth Amendment applies to searches (defined independently of their reasonableness) of persons, houses, papers and effects, and then only bars such searches if they are unreasonable.
In the Riley and Kyllo cases, the Supreme Court applied the Katz test and was able to reach sensible results. But because the Court employed the Katz test rather than the original meaning, one might wonder whether the original meaning could really be applied to this new technology.
To answer this question, let me start by discussing what I believe the Fourth Amendment’s original meaning is. Then, in my next essay, I will discuss how that might be applied in these two cases.
While Katz defines a search as any interference with the reasonable expectations of privacy of a person, the original meaning is different. As Justice Thomas’s dissent in Carpenter indicated, the original meaning of search seems to be the ordinary meaning at the time of “looking over or through” or “examining by inspection.” And the original meaning only covers searches of “persons, houses, papers, and effects.” But a key provision of the text is that it prohibits “unreasonable searches.” What does that mean? Many people have assumed that this language left the concept of reasonableness unclear and therefore amounts to a delegation to future judges.
But while the text—in the abstract—might seem like it could have that meaning, Laura Donahue has persuasively argued that an “unreasonable search” is a search that conflicts with the “reason of the common law.” In other words, searches that violate the common law rules for searches at the time of the Fourth Amendment are unreasonable searches. Thus, the Fourth Amendment incorporated the common law rules at the time and it did so with the language of “unreasonable searches.”
While this insight is extremely helpful, outstanding questions still remain. One question is whether this simply means that the Fourth Amendment adopts a constitutional common law approach, where the Court can decide what violates the Constitution based on evolving values over time. If that is the case, the Katz approach might not seem so problematic.
But that is not how the Fourth Amendment is properly interpreted. While the Fourth Amendment constitutionalizes the common law right, that does not mean it allows the Court to determine the content of this right by freely applying the common law method. If that were the case, the content of the right might change if there were a change in values or practices. The Amendment would then have constitutionalized a possibly evolving right. Instead, the Fourth Amendment adopts what the common law right was at the time of the Fourth Amendment and constitutionalizes that. The Amendment freezes the right as of the time of the Fourth Amendment.
If the Amendment were not interpreted as freezing the right, it would have a peculiar result. It would not assure the people that the right would protect them as strongly as it traditionally did under common law. Moreover, it would allow the Court extremely ample discretion. Traditional common law rights could be changed by ordinary statutes. But if the Fourth Amendment were not understood as freezing the right, a constitutional amendment would be required to change the common law as developed by the Supreme Court.
While interpreting the Amendment to freeze the right avoids these peculiar results, this still leaves an important question: What happens if there is uncertainty about the content of the right? For example, what if there were conflicting precedents or there were matters that were not addressed by the existing precedents? Here one must figure out what the common law right was as to these matters.
To determine the content of the common law right in such unclear cases, one must put oneself in the position of a common law judge at the time. Thus, one must engage in common law reasoning by considering court precedents, societal practices, and values of the people. That, after all, is how one determines the content of a common law right.
But to ensure that one is actually determining the content of the frozen common law right (rather than updating that common law right to take into account modern values), the interpreter must decide the case based on the precedents, practices, and values at the time of the Amendment. For example, if new values emerged 50 years after the Constitution was enacted, those values would not be legitimately considered by the interpreter when determining the content of the common law right.
This approach could be used to decide cases involving new technology. Since such technology did not exist at the time of the Constitution, the historical common law right did not specifically address it. In some cases, though, the new technology would seem to be unambiguously covered by the right. But in other cases, it might not. In these latter cases, determining the content of the right would require the use of common law reasoning. It would require the judge to determine how a common law judge at the time would have decided the case, given the values and circumstances at the time. This decision procedure is a way of determining the content of a frozen common law right when the content of that right is unclear.
In the case of modern technology, it might seem artificial to imagine how judges at the time of the Constitution would decide the case as applied to, for example cell phones. But as I argue in my next essay, there need not be anything problematic about this decision. While there may be hard cases, there will also be easy cases, as with any area of the law.