Final Version of “Defending Equilibrium-Adjustment”

The Harvard Law Review has just posted the final version of my response to Professor Slobogin’s critique of my recent article, An Equilibrium-Adjustment Theory of the Fourth Amendment. Here’s a short excerpt from my response, Defending Equilibrium-Adjustment:

Equilibrium-adjustment is not originalism. It is a theory of maintaining the status quo balance of power, not an effort to restore eighteenth-century rules. That understanding explains why living constitutionalists and pragmatists alike have embraced equilibrium-adjustment, and why the chief attack on it has been launched on originalist grounds. It is true, as Slobogin says, that the theory “harks back to some earlier time.” But that does not make it originalist. The relevant “earlier time” is a time before a triggering technological development, but it need not be the year the Fourth Amendment was ratified.

To be sure, it is possible for originalists to adopt the method of equilibrium-adjustment. But nonoriginalists can adopt it, too. In my view, its widespread appeal is what makes equilibrium-adjustment a valuable tool for understanding Fourth Amendment law: Justices from very different interpretive schools use it. It operates equally well within all of the different theories of interpretation. Different Justices might tailor the method based on their interpretive commitments. But they all can engage in equilibrium-adjustment, and almost all do. The Supreme Court’s recent decision in United States v. Jones provides a revealing illustration of how equilibrium-adjustment can occur in both originalist and nonoriginalist forms.
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The Supreme Court handed down Jones just a few weeks after my Article appeared, and the case divided the Court into two main camps. One adopted an originalist methodology; the other explicitly rejected originalism. But both approaches relied heavily on equilibrium-adjustment.
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The majority opinion by Justice Scalia engaged in equilibrium-adjustment using an originalist framework. When the Government argued that Jones had no reasonable expectation of privacy in the public location of the car, Justice Scalia responded that the Fourth Amendment should be read to protect rights beyond the reasonable expectation of privacy test. Quoting from his opinion in Kyllo v. United States,28 Justice Scalia reasoned that the Fourth Amendment must be interpreted to “assur[e] preservation of that degree of privacy against government that existed when the Fourth Amendment was adopted.” To assure preservation of that privacy, Justice Scalia interpreted the Fourth Amendment as protecting against common law trespasses. The installation of the GPS device with intent to use it to obtain information was a common law trespass, and therefore a Fourth Amendment search.

Justice Alito filed an opinion concurring in the judgment, joined by Justices Ginsburg, Breyer, and Kagan. Justice Alito criticized the majority’s originalist approach as inconsistent with precedent and unworkable. Instead, Justice Alito engaged in equilibrium-adjustment using the Katz “reasonable expectation of privacy” framework. He explained that “[i]n the pre-computer age,” surveillance that could reveal information as extensive as GPS monitoring was impractical in most cases. It would require “a large team of agents, multiple vehicles, and perhaps aerial assistance.” Changing technology had expanded government power by making such monitoring “relatively easy and cheap.” Accordingly, Justice Alito interpreted the Fourth Amendment to limit the government’s new powers. Although Justice Alito’s opinion is not a model of clarity, he seems to have interpreted the reasonable expectation of privacy test to lock in prior understandings of how invasive police investigations might be. Long-term use of GPS monitoring constituted a Fourth Amendment search because it exceeded pre-GPS societal expectations that such invasive monitoring was unlikely or even impossible.

Justice Sotomayor joined the majority opinion and filed a concurrence agreeing with and going beyond Justice Alito’s rationale. Like the opinions filed by Justices Scalia and Alito, Justice Sotomayor’s opinion engaged in equilibrium-adjustment. GPS monitoring “may alter the relationship between citizen and government,” Justice Sotomayor reasoned, and the Fourth Amendment had to be interpreted to limit use of “a tool so amenable to misuse.” Justice Sotomayor also expressed a need to revisit the third-party doctrine, the rule that information disclosed to third parties does not receive Fourth Amendment protection. That doctrine is “ill suited to the digital age,” Justice Sotomayor reasoned, given that now “people reveal a great deal of information about themselves to third parties in the course of carrying out mundane tasks.”

The three opinions in Jones proceed from different premises. One is originalist; two are not. But all three opinions rest on the principle of equilibrium-adjustment.