On October 11-13, I had the opportunity to participate in the Drones & Aerial Robotics Conference (DARC) at NYU Law. I served as Chair of the Drones and the Future of Public Space roundtable, which hosted Peter Asaro, Stuart Banner, Woodrow Hartzog, Marcel LaFamme, Greg McNeal, Paul Voss, and our moderator Greg Lindsay.
In light of the upcoming approval of commercial licenses by the Federal Aviation Authority (FAA) as of 2015, our roundtable explored how the law should conceptualize “public space” in relation to drones, and to what extent it should privatize or enclose portions of the “public highway” in favor of protecting privacy.
The framework for regulating airspace was established by the Supreme Court in United States v. Causby, which involved a takings claim under the Fifth Amendment. Causby displaced the old common law doctrine that land ownership extends to the periphery of the universe, replacing it with a conceptualization of airspace as a “public highway”. The Court reasoned that airspace must be a public highway, otherwise any flight passing over private property could result in a trespass suit. The Court qualified this finding by suggesting that an owner must have exclusive control over the immediate reaches of the atmosphere above his property in order to exercise full enjoyment of land. The factors that the Court established to determine the boundaries of public and private airspace include whether an aircraft is flying directly over an owner’s property, the altitude and frequency of the flights, and whether such flights interfere with an owner’s enjoyment of his property.
This Causby framework has been transported into trespass and nuisance tort claims involving airspace. For a trespass claim to succeed, the owner must establish that the intrusion occurred within the immediate reaches of the owner’s land, and that the intrusion resulted in interference with use and enjoyment of the land. In the case of a nuisance claim – while there is no requirement that an intrusion occur within the immediate reaches of one’s property – interference with use and enjoyment of property must be made out.
More troubling, is the application of Causby reasoning to Fourth Amendment case law involving airspace. In California v. Ciarolo, the Court found that there was no Fourth Amendment violation when police flew over an individual’s backyard to investigate marijuana growth because the observation occurred in “publicly navigable airspace” (as defined by the FAA). Similarly, in Florida v. Riley, the Court ruled that the Fourth Amendment was not violated when police flew over a greenhouse in a helicopter to investigate a marijuana grow-op because they were “where they had a right to be” (according to FAA guidelines regarding “navigable airspace” for helicopters). More peculiar than the fact that the Court relies on FAA guidelines designed to ensure safety to determine whether there is a reasonable expectation of privacy, is that the Court in Riley supported its finding by stating that the helicopter did not cause any undue noise, wind, dust or threat of injury.
This progressive mission creep of the Causby framework will be even more consequential to individual rights if applied in the context of drones. The FAA Modernization Act permits the FAA to regulate drone use in airspace below 400 feet. Presumably, small drones that don’t pose a significant threat to safety will be permitted to fly at very low altitudes. Applying the Causby analysis, when such drones will be operated within the FAA definition of “navigable airspace” and there is no interference with use and enjoyment of land, it will be very difficult to establish Fifth Amendment, trespass, nuisance and Fourth Amendment claims.
I suggest that the law must evolve beyond the public vs. private space dichotomy that was enshrined in Causby, and that it ought to enclose portions of the public highway in order to protect privacy. To be clear, I am not suggesting a complete privatization of public airspace granting the ultimate stick in the bundle – the right to exclude – that the Causby Court was rightfully concerned about. Instead, I propose a contextualized enclosure of public space that simultaneously recognizes a public right of access and an individual right to privacy. This proposal is compatible with the general shift in law from the reductive Blackstonian characterization of property as the right to exclude, to a more nuanced conceptualization of property as a bundle of rights.
If we accept that private property is a bundle of rights, we must also accept that public property – including public airspace – is a bundle of rights. The famous architect and urban space designer Stephen Carr suggested that the bundle of rights in public space includes the right to access, freedom of action (which must be “responsible action” as public space is shared) and even the right to claim a proprietary interest – a degree of spatial control – that is necessary to attain the goals of public space. Carr relied on Alan Westin’s four states of privacy to substantiate his argument that we have a right to claim certain individual interests in public space such as anonymity and intimacy.
If we apply the bundle of rights metaphor to airspace, I suggest that we can disaggregate the privacy interest from the right to exercise exclusion of others. The practical implications for drone use are that airspace remains public – no one has a right to exclude others – however we recognize a contextualized enclosure that makes room for a privacy interest.
As a thought experiment, let’s apply the contextualized enclosure of public space framework to the fact scenario in Florida v. Riley. The Court’s analysis of Riley’s reasonable expectation of privacy would exclude the fact that the police were flying at an acceptable altitude according to FAA regulations, and that the helicopter did not cause any undue noise, wind, dust or threat of injury. It’s difficult to predict whether a different outcome would occur applying this framework (as doing so would cause the Court to engage in a more nuanced approach to determining what is a reasonable expectation of privacy in public), but what is certain is that the framework would remove factors that don’t seem to have a legitimate place in Fourth Amendment analyses.