Before the decade is out, there may be thousands more eyes in the sky. Unmanned aerial vehicles, commonly known as drones, are already a staple of modern warfare. Now they are set to take on a much larger role in the U.S.
Congress has directed the Federal Aviation Administration to set rules by 2015 for how drones may be used in domestic airspace. These rules could open up the skies to unmanned vehicles of all types—from large surveillance drones used by the military to insect-size prototypes being developed in university laboratories. The technology promises to be immensely useful. Public safety agencies can use drones to survey wildfires, conduct search-and-rescue operations, or pursue heavily armed suspects. Farmers will use them to survey their fields; energy companies will fly drones over critical machinery.
Still, drones also pose an immense threat to privacy. The proliferation of small, inexpensive aerial vehicles with video downlinks will dramatically alter the cost-benefit ratio of surveillance. No longer will law-enforcement agencies need to consider the expense and risk of operating a helicopter when gathering evidence. Consequently, law-enforcement agencies will have ample opportunity and motivation to deploy drones on open-ended sorties. It is not hard to imagine blanket campaigns that survey entire cities for backyard marijuana plants or even building code violations. Privacy advocates rightly worry that drones, equipped with high-resolution video cameras, infrared detectors and even facial-recognition software, will let snoops into realms that have long been considered private.
The privacy threat does not just come from law enforcement, either. Paparazzi and private detectives will find drones just as easy to use as the cops. Your neighbor is not allowed go into your yard without your permission—will he be able to keep a drone hovering just above it?
Case law paints a hazy picture of how drones could be employed for surveillance. A 1989 Supreme Court decision ruled that police may use helicopters to peer into semiprivate areas—say, the backyard of a home—without first obtaining a warrant. Such speculative reconnaissance, however, has been naturally limited by the costs of helicopter operations. Will the same law apply to unmanned drones, which are not similarly constrained?
A more recent case poses troubling questions about access to the most sacrosanct spaces. In 2001 the Supreme Court ruled that police could not use thermal-imaging technology to gather evidence about the goings-on hidden inside a residence without first obtaining a warrant. The court reasoned that governmental use of “a device that is not in general public use”—a thermal imager—constitutes a search under the Fourth Amendment and therefore requires a judge's approval. Yet if unmanned aerial vehicles become as prevalent as manufacturers hope, one could argue that drones are exempt from that precedent.
Already the faa has permitted a handful of law-enforcement agencies to operate drones on a short-term basis. The limited regulations accompanying those permits (which, thankfully, preclude attaching any weapons to the drones) are insufficient to protect the privacy of citizens. Perhaps this should not be surprising. The faa is not in the business of privacy protection. Its primary concern is with the safety of domestic airspace.
No federal agency, in fact, can be held accountable if drones are not used responsibly and in a way that respects the Fourth Amendment. As such, Congress should proactively enact laws that confine domestic drones to reasonable, useful purposes. Several sensible ideas were proposed during the last session of Congress, including a bill that would have outlawed drone spying without a warrant and instituted important transparency and accountability measures for their use. But that bill failed to make it out of a subcommittee. The present Congress must be more active than its predecessor in heading off this clear and impending threat to personal privacy.