Observations from Above: Unmanned Aircraft Systems and Privacy

III. GOVERNMENT UNMANNED AIRCRAFT AND THE FOURTH AMENDMENT The Fourth Amendment is central to the privacy issues with respect to government UAS operation. Although the Supreme Court has never explicitly considered the question of UAS privacy, there is a long list of relevant precedents. (90) Among them are several cases from the 1980s that specifically considered aerial observations and the Fourth Amendment. The 2001 Kyllo v. United States (91) and 2012 United States v. Jones (92) decisions are also pertinent. A. Dow Chemical Co. v. United States In 1978, the Environmental Protection Agency, without Dow Chemical's consent, contracted with a commercial aerial photographer to provide images of a 2000-acre Dow Chemical manufacturing facility from altitudes of 1200, 3000, and 12,000 feet. (93) When Dow Chemical became aware of this, it filed suit in Federal District Court, which granted summary judgment, finding the aerial photography to be a search in violation of the Fourth Amendment. (94) The Sixth Circuit reversed the decision, ruling that even though the company had taken precautions, including installing a perimeter fence and alarm system (95) that provided a subjective expectation of privacy from ground-level intrusions, it did not have such an expectation with respect to aerial surveillance. (96) Thus, the Sixth Circuit concluded, the acquisition of aerial images without a warrant was not a Fourth Amendment search. (97) In reviewing this ruling on certiorari, the Supreme Court affirmed the Sixth Circuit's decision, concluding in a 1986 ruling that the open areas in the 2000-acre industrial facility were more akin to an "open field" (98) than to the curtilage of a home, and, as a result, were "open to the view and observation of persons in aircraft lawfully in the public airspace immediately above or sufficiently near the area for the reach of cameras. " (99) The Court also noted the role of technology diffusion as a factor, writing that "surveillance of private property by using highly sophisticated surveillance equipment not generally available to the public, such as satellite technology, might be constitutionally proscribed absent a warrant. " (100) However, the Court observed, "[a]ny person with an airplane and an aerial camera could readily duplicate" (101) the photographs at issue. "[T]he taking of aerial photographs of an industrial plant complex from navigable airspace is not a search prohibited by the Fourth Amendment. " (102) B. California v. Ciraolo Ciraolo (103) was decided in 1986, on the same day as Dow Chemical. On September 2, 1982, police in Santa Clara, California, received a tip regarding backyard marijuana cultivation. (104) After finding the yard surrounded by high fencing obscuring the view from the street, they obtained a small airplane and flew over the residence at 1000 feet. (105) The officers on the airplane observed and photographed what they concluded to be marijuana plants growing in the backyard. (106) This evidence was used to obtain a search warrant to seize the plants. (107) The Supreme Court granted certiorari after the California Court of Appeal ruled that the warrantless aerial observations violated the Fourth Amendment. (108) In May 1986, the Supreme Court issued a five-to-four decision reversing the lower court. (109) Writing for the majority, Chief Justice Burger framed the analysis in terms of the "reasonable expectation of privacy" (110) articulated in Justice Harlan's concurrence in Katz. (111) For an expectation of privacy to be "reasonable" under Katz, two separate criteria must be satisfied. First, the person must "have exhibited an actual (subjective) expectation of privacy. " (112) Second, the expectation must "be one that society is prepared to recognize as 'reasonable. "' (113) With respect to the first criterion, the Ciraolo Court wrote that although the presence of fences clearly conveyed a "desire to maintain privacy," and indeed successfully did so with respect to "normal sidewalk traffic," the marijuana plants might well have been visible from a truck or two-level bus. …