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Fourth Amendment

Government Drone Overflights May Violate Fourth Amendment, Trigger Exclusionary Rule

An interesting Michigan appellate decision.

|The Volokh Conspiracy |


From Long Lake Township v. Maxon, decided March 18 by the Michigan Court of Appeals (Judge Kathleen Jansen joined by Judge Amy Ronayne Krause):

In 2008, the parties litigated an alleged violation of the Long Lake Township Ordinance by defendants. That proceeding culminated in a settlement agreement …. In 2018, plaintiff filed the instant civil action, alleging that defendants had "significantly increased the scope of the junk cars and other junk material being kept on their property" since entering into the 2008 Agreement, and that such activity "constitut[ed] an illegal salvage or junk yard" in violation of the Long Lake Township Zoning Ordinance. In support of these allegations, plaintiff attached aerial photographs taken in 2010, 2016, 2017, and 2018. These photographs showed a "significant increase in the amount of junk being stored on [d]efendants' property."

Defendants moved to suppress the aerial photographs and "all evidence obtained by [p]laintiff from its illegal search of their property." Defendants argued that the aerial surveillance of their property, and the photographs taken by the drones of their property and the surrounding area, constituted an unlawful search in violation of the Fourth Amendment.

Defendants argued that the instant case is distinguishable from precedent involving manned aerial surveillance because, unlike fixed wing aircraft and helicopters which "routinely fly over a person's property," drones are equipped with "high power cameras" and do not operate at the same altitudes as airplanes and helicopters. Additionally, defendants argued that a person can reasonably anticipate being observed from the air by a fixed wing aircraft, but aerial surveillance from a drone flying over private property and taking photographs is not a reasonable expectation. Moreover, defendants noted that plaintiff's drone surveillance did not comply with Federal Aviation Administration (FAA) regulations. We note that photographs in the record clearly show that very little, if any, of defendants' property is visible from the ground, due to a combination of buildings and trees….

This is ostensibly a civil proceeding…. However, the Fourth Amendment may protect parties from unreasonable searches and seizures committed by a governmental entity in civil cases, if the civil case can be considered "quasi-criminal" and the search or seizure was committed by the governmental entity pursuing the action. Kivela v. Dep't of Treasury (Mich. 1995) (discussing a test for the admissibility of evidence illegally seized by police for a criminal proceeding in an independent subsequent tax proceeding); People v. Gentner, Inc. (Mich. App. 2004); see also Camara v. Muni. Court of City and Co. of San Francisco (1967) (holding that administrative searches implicate the Fourth Amendment even if the searches are not criminal in nature, albeit subject to less exacting requirements to establish probable cause)….

The purpose of this litigation is to obtain a declaratory judgment that defendants' use of their own property is illegal. Considering the great historical importance placed on the freedom to use one's own property, and the fact that the consequences of this action may entail far more than merely the imposition of money damages, we conclude that this is the kind of proceeding to which the Fourth Amendment may apply. Further supporting this conclusion is MCL 259.322(3), which expressly prohibits the use of a drone to "capture photographs, video, or audio recordings of an individual in a manner that would invade the individual's reasonable expectation of privacy."

In Kyllo v. United States (2001), Justice Scalia [wrote]:

… The present case involves officers on a public street engaged in more than naked-eye surveillance of a home. We have previously reserved judgment as to how much technological enhancement of ordinary perception from such a vantage point, if any, is too much. While we upheld enhanced aerial photography of an industrial complex in Dow Chemical, we noted that we found "it important that this is not an area immediately adjacent to a private home, where privacy expectations are most heightened." …

Critically for the instant matter, the Court opined that mere existence and availability of technological advancements should not be per se determinative of what privacy expectations society should continue to recognize as reasonable. Although again discussing only privacy within the home, the Court emphasized that the homeowner should not be "at the mercy of advancing technology" that might eventually be able to see directly through walls outright. The development of historically-novel ways to conduct unprecedented levels of surveillance at trivial expense does not per se reduce what society and the law will recognize as a reasonable expectation of privacy.

In California v. Ciraolo (1986), the United States Supreme Court determined "whether the Fourth Amendment is violated by aerial observation without a warrant from an altitude of 1,000 feet of a fenced-in backyard within the curtilage of a home." In that case, a law enforcement officer used an airplane, flown at an altitude of 1,000 feet, to observe the respondent's yard, which was next to the respondent's home and enclosed by a fence. The officer identified marijuana plants in the respondent's yard and used a camera to photograph the area, and the images were used to secure a warrant…. The Court determined that the officer's observations took place within public navigable airspace, in a physically nonintrusive matter, and that "[a]ny member of the public flying in [the] airspace who glanced down could have seen everything that these officers observed." The United States Supreme Court concluded, "[i]n an age where private and commercial flight in the public airways is routine, it is unreasonable for respondent to expect that his marijuana plants were constitutionally protected from being observed with the naked eye from an altitude of 1,000 feet."

Only a few years later, in Florida v. Riley (1989), the United States Supreme Court held, in a plurality opinion, that police observation of a greenhouse, located in respondent Riley's curtilage, from a helicopter at an altitude of 400 feet did not violate the Fourth Amendment….

As defendants tacitly concede, Ciraolo and Riley establish that defendants could not have reasonably expected the activities and items on their property to be protected from public or official observation made by a human being from the publicly navigable airspace. Conversely, unrefuted photographic exhibits of defendants' property taken from the ground seem to establish a reasonable expectation of privacy against at least casual observation from a non-aerial vantage point. We conclude that; much like the infrared imaging device discussed in Kyllo; low-altitude, unmanned, specifically-targeted drone surveillance of a private individual's property is qualitatively different from the kinds of human-operated aircraft overflights permitted by Ciraolo and Riley. We conclude that drone surveillance of this nature intrudes into persons' reasonable expectations of privacy, so such surveillance implicates the Fourth Amendment and is illegal without a warrant or a traditional exception to the warrant requirement.

Although noncompliance with FAA regulations does not establish a Fourth Amendment violation, such regulations are relevant to what a person might reasonably expect to occur overhead. Persons may, absent extraordinary circumstances, reasonably expect the law to be followed, even if they know the law is readily capable of being violated.

The FAA regulations require drone operators to keep drones within visual observation at all times, fly drones no higher than 400 feet, refrain from flying drones over human beings, and obtain a certification. Such rules reflect the fact that drones are qualitatively different from airplanes and helicopters: they are vastly smaller and operate within little more than a football field's distance from the ground. A drone is therefore necessarily more intrusive into a person's private space than would be an airplane overflight.

Furthermore, unlike airplanes, which routinely fly overhead for purposes unrelated to intentionally-targeted surveillance, drone overflights are not as commonplace, as inadvertent, or as costly. In other words, drones are intrinsically more targeted in nature than airplanes and intrinsically much easier to deploy. Furthermore, given their maneuverability, speed, and stealth, drones are—like thermal imaging devices—capable of drastically exceeding the kind of human limitations that would have been expected by the Framers not just in degree, but in kind.

Although the United States Supreme Court rejected the ancient understanding that land ownership extended upwards forever, landowners are still entitled to ownership of some airspace above their properties, such that intrusions into that airspace will constitute a trespass no different from an intrusion upon the land itself. Drones fly below what is usually considered public or navigable airspace. Consequently, flying them at legal altitudes over another person's property without permission or a warrant would reasonably be expected to constitute a trespass.

We do not decide whether nonpermissive drone overflights necessarily are trespassory, because we need not decide that issue. Although a physical trespass by a governmental entity may constitute a violation of the Fourth Amendment, a trespass into an open field might not implicate the Fourth Amendment. Furthermore, we think there is little meaningful distinction for present purposes between "just inside the property line" and "just outside the property line."

We decide this matter based upon defendants' reasonable expectation of privacy—critical to which is that any reasonable person would have expected a low-altitude drone overflight to be trespassory and exceptional, whether the drone flew as high as a football-field length or flew directly up to an open bathroom window. The Legislature has already stated that drones may not be used to violate a reasonable expectation of privacy, MCL 259.322(3), or to perform an act that would be illegal if performed by the operator in person, MCL 259.320(1)….

We also observe that plaintiff's warrantless surveillance was totally unnecessary. The parties could easily have—and likely should have—included a monitoring or inspection provision in their settlement agreement. Aside from that, as the United States Supreme Court observed, the quantum of evidence necessary to establish probable cause to conduct an administrative inspection is more than "none," but is less than what might be required to execute a criminal search warrant.

By plaintiff's own account, it had concrete evidence, in the form of unrelated site inspection photographs and complaints from defendants' neighbors, that defendants were violating the settlement agreement, violating the zoning ordinance, and creating a nuisance. Our holding today is highly unlikely to preclude any legitimate governmental inspection or enforcement action short of outright "fishing expeditions." If a governmental entity has any kind of nontrivial and objective reason to believe there would be value in flying a drone over a person's property, as did plaintiff here, then we trust the entity will probably be able to persuade a court to grant a warrant or equivalent permission to conduct a search….

Judge Karen M. Fort Hood dissented, arguing that Ciraolo and Riley were controlling here, and Kyllo didn't apply because drones were indeed in common use:

[D]rones are generally widely available to the public {[t]here were 873,144 drones registered with the FAA as of February 2021}, there is reason to believe that the public commonly flies them at altitudes of 400 feet and below, and there is no evidence in this case that the drone in question was flying at a particularly invasive altitude or in a particularly invasive manner, or that the drone contained or used any particularly invasive technology. Similar to Ciraolo and Riley, there is reason to believe that any member of the public could have used their own drone and plainly viewed the property at issue in this case…. I would emphasize the common availability and use of drones by the public in determining whether defendants had a reasonable expectation of privacy in this case. That, in conjunction with whether the drone in this case was lawfully deployed in the public airspace, should control over our policy concerns with respect to how drones may be operated in future cases….

The fundamental principle from both Ciraolo and Riley is that the property observed in those cases was observable by commercial and public aircraft in the publicly navigable airspace, and the fundamental difference between those two cases and Kyllo was that the technology in Kyllo was not something that could be reasonably expected to be employed by members of the public. On that basis, I would conclude that no Fourth-Amendment violation occurred in this case, and I would affirm the trial court's order denying defendants' motion to suppress.