I recently finished a very rough draft of a new paper, Four Models of Fourth Amendment Protection, in which I explain the “reasonable expectation of privacy” test by relying on four competing models of Fourth Amendment protection. They are the norms model, which matches rules to social expectations; the privacy model, which attempts to measusure the invasiveness of law enforcement activity; the property model, which tracks property law; and the consequences model, which looks to the practical consequences of the court’s legal rule. In my paper, I argue that the Justices mix and match among all four models when they apply the “reasonable expectation of privacy” test, and that they have not chosen a single model for a very good reason: no single model consistently applied would generate a satisfactory set of results. As a result, existing Fourth Amendment law reflects an inevitable tension among these four different models.
Today’s opinions in Georgia v. Randolph provided an unusually clear demonstration of the competing models, albeit technically in the context of when a search is “reasonable” rather than the preliminary question of what is a “search.” For example, the majority opinion by Justice Souter rejects the property model in favor of the norms model. The key passage:
The constant element in assessing Fourth Amendment reasonableness in the consent cases, then, is the great significance given to widely shared social expectations, which are naturally enough influenced by the law of property, but not controlled by its rules. Cf. Rakas v. Illinois, 439 U. S. 128 , n. 12 (1978) (an expectation of privacy is reasonable if it has “a source outside of the Fourth Amendment, either by reference to concepts of real or personal property law or to understandings that are recognized and permitted by society”). Matlock accordingly not only holds that a solitary co-inhabitant may sometimes consent to a search of shared premises, but stands for the proposition that the reasonableness of such a search is in significant part a function of commonly held understanding about the authority that co-inhabitants may exercise in ways that affect each other’s interests.
In his dissent, Chief Justice Roberts derides the norms model as “a hunch,” and instead would follow a privacy model: Having shared space with a third party, he argues, the person has given up their right to privacy and cannot object if the third party consents to a search. Roberts also relies on the consequences model, explaining his view that the majority’s rule is bad because it will impede domestic violence cases. Meanwhile, Justice Stevens and Justice Scalia duke it out in solo opinions on the role of the property model in Fourth Amendment law.
All of this is to suggest that there is a lot of interesting stuff in Randolph: it’s a pretty rich set of opinions at a variety of levels, and touches on a couple of major fault lines that I think are at the core of the modern Fourth Amendment. I hope to blog a lot about it (and Grubbs, too) over the next few days, as there are lot of tidbits in there to mull.