Popular Conceptions of Fourth Amendment Curtilage

I’m very happy to post a draft of a new article, “Popular Conceptions of Fourth Amendment Curtilage,” written together with my co-author Matthew Kugler, forthcoming in the Michigan Law Review.

The article picks up an idea I first pondered here at the Volokh Conspiracy back in 2018. The Supreme Court interprets the Fourth Amendment to extend the privacy of the home beyond the home’s walls to an outside space it calls “curtilage,” and it insists that what counts as curtilage, and the implied license to enter it, is intuitive and widely known. But is it? What do ordinary people really think about curtilage and implied license?

Here’s the abstract of our new article:

Fourth Amendment protections outside depend on a legal concept called “curtilage.” Entering the curtilage of a property normally requires a warrant unless the entry is within an implied license. According to the Supreme Court, the boundaries of curtilage and implied license are found largely in prevailing social norms—what the Court calls “the habits of the country.” Judges tasked with applying curtilage doctrine are supposed to intuit these shared attitudes to determine what the police can and cannot do. But there is something missing: No one has ever asked the public what they think.

This Article presents the results of three empirical studies, involving 600 participants each, in which members of the public were asked what places count as curtilage and what visits to homes are covered by implied license. In the first two studies, survey participants were shown a series of images of various properties with an officer present and answered whether the officer was inside or outside the curtilage. In the third study, participants were given a set of home-visit scenarios and answered whether each visit was within or outside the implied license. The surveys covered the facts of both Supreme Court cases and prominent lower court decisions to see if the courts have it right.

We found that the courts have curtilage wrong but implied license right. In the doctrine, curtilage is limited to the area immediately around the home. But the public disagrees. To most people, privacy in the home extends to the entire property. If it’s part of the property, it’s private. In short, the public has a far more expansive conception of home privacy than courts allow. On the other hand, public perceptions of implied license very closely align with the caselaw. Courts have misunderstood curtilage, but they have accurately described the implied license. Going forward, Fourth Amendment law should change: Courts should either justify current curtilage protection on different rationales or else expand the curtilage line to match public opinion.

This is just a draft, so comments are very welcome.