The Volokh Conspiracy
Mostly law professors | Sometimes contrarian | Often libertarian | Always independent
As I mentioned recently, I spent the last three months re-writing the Fourth Amendment materials for the Kamisar LaFave and Israel Criminal Procedure casebook for the 16th edition that will be available for use this coming fall semester. The biggest challenge of writing Fourth Amendment materials in a casebook is how to cover what counts as a Fourth Amendment "search." I thought I might write about what I think the challenge is, and how I restructured the existing material for the new edition.
Here's the problem. The Fourth Amendment prohibits unreasonable searches and seizures, and there is a dizzying amount of caselaw on what is a search. There are probably 50 or 60 major Supreme Court rulings on the question, and gobs of lower court cases. Further, the test itself is murky. The most often used test is the Katz "reasonable expectation of privacy" test, but the cases on that are confusing. The Supreme Court sometimes treats that test as a normative inquiry, sometimes as a descriptive inquiry, and when it's descriptive it divides over what it's describing. Then you add the trespass test, which is maybe (or maybe not) just a physical intrusion test — no one really knows, it depends on the judge — that does an uncertain amount of work in addition to the privacy test. To top it off, the results need to give students clarity about where officers can go and what they can do in a wide range of situations. How on earth do you cover that, especially if you only have 60 pages or so in which to do it?
I thought a lot about that question this fall, and here's the approach I adopted.
First, some context. In an introductory section, before the search materials begin, students will have already learned that the problems that inspired the Fourth Amendment involved physical intrusion into physical spaces — most often, searching houses in the literal sense of breaking in to them and physically rifling through their contents. The key question is, what beyond that foundational scenario is also covered as a search?
As I assembled the materials, I addressed that in four sections: Introduction to Katz; privacy in physical spaces; problems of new technology; and the trespass/intrusion test.
The first section, about 10 pages long, introduces the reader to Katz v. United States, which was the Warren Court's main case on what (if anything) beyond physical intrusion is covered as a search. Katz, and Harlan's concurrence, introduce the reasonable expectation of privacy test. Then the notes after Katz introduce some of the key conceptual questions around that: Just what is the Katz test asking? How does it relate to the text? What is the role of the subjective test? The notes also inform the reader of some of the common and repeated applications of the test: When is it is a search to get information about the inside of a car? What about a package? The point of this first section is to just get a basic bearing on what the Katz test is.
The second section, which is about 15 pages, considers how Katz applies in physical space. The point of this section is to make sure students understand how Katz applies in the non-technological scenarios of an officer just walking around and seeing physical things. Where can officers go in ordinary physical space before their conduct becomes a search? It starts with a case on the open fields doctrine, United States v. Dunn, to explain the curtilage/open-fields distinction. Notes then cover how the Katz test applies in common physical spaces like entering businesses (that may be open or closed to the public), entering common areas of apartment buildings, and entering government offices. We then get California v. Greenwood, the trash case, and notes how the Katz test applies to searches of abandoned property, searches of jail cells, and searches of property belonging to people experiencing homelessness.
The third section takes on Katz and changing technology. A lot of the harder Katz issues are about technology, as technology changes the relationship between place and information and how easy it is to collect information. So this is the longest section, about 25 pages. The materials start with cases on technology-enhanced surveillance of physical spaces and then turn to network surveillance. The materials on technology-enhanced surveillance of physical spaces bookend California v. Ciraolo (aerial surveillance of a home, not a search), and Kyllo v. United States (thermal imaging of a home, a search). The related notes consider variations on this theme, such as dog sniffs, physical tracking devices, and abandoned DNA. The network surveillance cases then bookend Smith v. Maryland (numbers dialed, not a search) and Carpenter v. United States (cell-site location information, a search). The related notes consider variations such as accessing emails and IP addresses, short-term location tracking, and lower court interpretations of Carpenter. The "bookend" approach includes two major cases that seem to present similar kinds of issues but come out differently; the contrast invites the reader to consider why the Court decided them differently, and thus what matters in the doctrine. I think it works well for this particular material.
The final section, about 10 pages long, covers the trespass/intrusion test of United States v. Jones in 2012 and Florida v. Jardines in 2014. In addition to covering those two cases as "main" cases, notes focus on what the test is (Is it a trespass test as in torts? Is it a physical intrusion test, a return to pre-Katz caselaw?); how lower courts have applied it in ways that might go beyond Katz (to scenarios like chalking a tire and inserting keys in locks); and where it might go next (covering Justice Gorsuch's opinion on the "traditional approach" in Carpenter).
There are an endless number of ways to teach the search materials. As I said at the beginning, I think it's a tremendously challenging topic to cover. So I don't claim to have found the one and only way to present these materials. But my hope is that this format will click the most for students and professors alike. My hope is that this is as conceptually clear as it can be, in that it breaks down the issues for students in what I hope are helpful ways (covering physical cases vs. technology cases, Katz vs. trespass/intrusion, etc.). And the approach very roughly tracks the chronological order in which the cases were decided, so students can appreciate the development of the law and understand how later cases are built on (or break from) earlier ones.