In the 1980s, the Supreme Court issued two decisions that remain the prevailing authority on law enforcement’s practice of warrantless, aerial surveillance. In California v. Ciraolo, the Court held that a police officer lawfully observed marijuana plants when he flew, at an altitude of 1,000 feet, over a suspect’s backyard in a chartered plane. Later, in Florida v. Riley, the Court reached the same conclusion when officers used a helicopter to observe a marijuana-grow operation in a greenhouse from 400 feet. In short, the Court held in both cases that the Fourth Amendment does not require police to obtain a warrant before observing what any other member of the public could with the naked eye — even when that observation takes place at high altitudes in the public airspace.
At first glance, Riley and Ciraolo do not appear to pose much of a problem for law enforcement’s warrantless use of drone surveillance, but there are several distinctions that may lead the Court to depart from its earlier aerial surveillance decisions. First, drones use modern imaging and recording systems, not “the naked eye,” to capture images and data that its operator wishes to observe. Second, the majority opinion in Riley cited the fact that “no intimate details connected with the use of the home or curtilage were observed” in the helicopter fly-over. It is this second point that touches on the likely future of the constitutional controversy regarding drones: They give law enforcement an affordable and relatively surreptitious means through which to observe even the most intimate details of the activity on both public and private property, and it is unclear whether the existing battery of case law is instructive in addressing the constitutionality of such use.
The Supreme Court’s 2012 decision in United States v. Jones addressed the constitutionality of around-the-clock monitoring, via GPS, of a suspect’s vehicle, and is illustrative of the Court’s potential to depart from its earlier warrantless-surveillance holdings. While the Jones Court invalidated the surveillance based on physical trespass principles, justices Samuel Alito and Sonia Sotomayor authored separate concurrences acknowledging the constitutional question raised by recent technology’s ability to allow law enforcement to conduct inexpensive and extended surveillance of citizens. It is not difficult to imagine a similar set of facts as seen in Jones, only this time involving a drone, appearing before the Court and challenging the sufficiency of 20th Century precedent to 2014’s technological reality.
