"In the states that don't require warrants, it's pretty much a Wild West" in terms of what's allowed, says Jay Stanley, senior policy analyst at the American Civil Liberties Union. "There's nothing stopping a police department from using [drones] in all kinds of ways to spy, except for the Constitution."
Within that unregulated "Wild West," police have very different approaches to their drone programs. One of the longest-running law enforcement drone programs is at the Mesa County Sheriff's Office in Colorado. Ben Miller, its director, says the department has a 17-page policy that outlines when and how it can use drones and for how long it retains data.
The department has never run a surveillance mission with its drones, Miller says, which are generally used for search-and-rescue and crime-scene photography. "If we had a need to look into an area where someone would have a legitimate expectation of privacy, we'd get a warrant," he says.
Colorado is one of the states without any legislation about drones at all, according to the National Conference of State Legislatures, which means that the limitations on the Mesa County drone program were instituted at the department's prerogative.
Unlike the Mesa County Sheriff's Office, some law enforcement agencies have been less than forthcoming with their drone programs. Last year, the San Jose Police Department in California secretly bought a $7,000 drone, and was faced with uproar in the community when freedom-of-information requests brought the purchase to light six months later.
The police department said the drone was meant for helping bomb technicians access hard-to-reach places, but left the door open for using the drone to address "dangers such as active shooters, hostage taking, or other such tactical situations where lives might be in immediate danger."
And this December, the sheriff in Alameda County, Calif., revealed that he spent $97,000 of his own department's money to buy a pair of drones after he was barred from using federal funds to make the purchase. The sheriff told the San Francisco Chronicle that the drone won't be used for surveillance "in any shape, manner or form," but California, like Colorado, has no state law that requires warrants for surveillance.
The California state assembly passed a bill last year that would have required police to obtain a warrant to fly drones in any event other than an "emergency situation." But Gov. Jerry Brown vetoed it in September, because he said the exceptions the bill allowed "appear to be too narrow."
While advocates are worried that law enforcement could use drones in ways that violate citizens' privacy, there's little fear that they're being abused yet. "Safety restrictions are so strict that most police departments are still using them in quite limited ways," the ACLU's Stanley said. "This is still an issue of looking down the road to what we know is coming."