Right now, in the United States, law enforcement can put you under drone surveillance without a warrant โ€” as long as the drone never lands on your property. What the hell is going on here? How can this be legal?

First of all, let me assure you that this kind of surveillance is going on right now. Law enforcement can choose to watch you with a drone, and they don't have to get permission from a judge (AKA a warrant) to do it.


The FBI recently sent a letter detailing their drone surveillance practices to Senator Rand Paul. Paul wanted to know how the agency justified using drones in this way under current privacy law. The FBI's Stephen D. Kelly replied that the FBI believes that people watched by drones do not have "reasonable expectation of privacy" because "there is no physical trespass involved." So if a drone hovers quietly above your backyard, filming everything you do, it's just fine โ€” because it never actually touched your personal property.

Privacy as Trespass

This disturbing little rule comes to you via a very literal interpretation of U.S. privacy laws. Most of our laws associate violation of privacy with trespassing. It makes sense, when you think about it. For most of U.S. history, a person had to walk onto your property or search your person into order to gain access to your private stuff. But over the past couple of decades, trespass has started to seem like a metaphor for privacy that's "from the past," as Roy on The IT Crowd would say.

In fact, "trespass" is a terrible way to think about privacy violation, according to Parker Higgins, an activist with the Electronic Frontier Foundation. Technologies like drones make it obvious that FBI agents can peep into your windows without walking into your backyard. "It was once a fact that trespass served as a good proxy for [privacy], Higgins told io9. "Increasingly we see examples that that proxy has failed."

Higgins thinks the drone rule is a perfect example of this failure. "Whether the drone touches down or not is irrelevant to most people," he said. "They're not offended that it touched down. They're offended that it's invading their privacy."

The Third Party Doctrine

But how did we even reach this point of absurdity, where the FBI can argue that they don't need a court's permission to look inside your windows because they aren't landing on your lawn to do it?


In their letter to Paul, the FBI rep mentions a famous Supreme Court decision from 1979 called Smith v. Maryland, which provided the foundation for what lawyers today often call the "third party doctrine." In that case, a man named Smith had robbed a woman and then proceeded to stalk her and make threatening phone calls. The police nabbed him by asking the phone company to tell them what numbers their suspect had called. It turned out that Smith had been calling the victim repeatedly, and they were able to make the arrest.

Smith argued that his privacy had been violated when the police asked the phone company to furnish them with what he believed were his "private" phone records. The court wasn't buying it. He had no reasonable expectation of privacy, the argued, because he'd turned that information over to the phone company. It wasn't on his property, and it wasn't on his person. So it wasn't private. In their decision, one justice wrote that "this Court consistently has held that a person has no legitimate expectation of privacy in information he voluntarily turns over to third parties."


Today, the FBI is able to use this idea to justify their unwarranted drone surveillance because the court ruled that people should expect less privacy protection for anything that isn't on their bodies or in their homes. The drone spies are just the most extreme example of how this works.


Mostly, the third party doctrine has become influential in recent years because courts are grappling with so many cases where people are storing what they consider private information with third parties. Think about your web mail, Skype conversations, Swarm check-ins, or privacy-locked Instagram photos. Those are all stored with third parties, and until recently a law enforcement officer could take a look at most of them without a warrant.

"We've got this concept of personal space being private, but it's not limited to your space anymore," explains Higgins. "Your space extends via high frequency signals to servers and clouds. Law enforcement recognizes this. That's why they want this information."


What Do You Expect to Be Private?

One of the bedrock ideas that shapes U.S. citizens' idea of privacy comes from the Fourth Amendment to the U.S. Constitution, which protects citizens from "unreasonable searches" by the government. The Amendment also says that a warrant should be issued to law enforcement only after they have established "probable cause." It wasn't until 1967 that the Supreme Court reinterpreted this Amendment to mean that people should be guaranteed "a reasonable expectation of privacy" even outside their homes.


When it comes to understanding privacy, many courts are still struggling to figure out what "reasonable expectation of privacy" means in a world of drones and digital archives.

But over the last few years, a new definition of privacy has begun to emerge. A couple of weeks ago, the Supreme Court issued a crucial decision in Riley v. California which will require law enforcement officers to get a warrant before searching people's cell phones for everything from text messages to GPS data. This extends our "reasonable expectation" of what's private to information stored with the phone company, with Google, or in your Lyft app. It also extends our protection from "unreasonable searches" from government.


AP Photo/Damian Dovarganes

Another landmark case in this area is U.S. v. Jones, a 2012 decision where the Supreme Court ruled that putting a GPS tracker on somebody's car is in fact a "search." Of course we can't reasonably expect that we are in private when we're driving down the street. But observing a car as it passes by is very different from attaching a device to it and following the car's every movement. At that point, the GPS device is being used to tail a suspect, and that requires a warrant.


But courts aren't the only institutions preventing us from having the privacy we reasonably expect. There is also a digital divide when it comes to how we think about privacy. People who grew up socializing online don't understand privacy in the same way as people who didn't. As danah boyd explains in her indispensable book about online youth culture, It's Complicated, today's teens use social media to supplement real-life friendships. Conversations that high schoolers in the 1980s would have had in whispers behind cupped hands are now happening on Snapchat and Facebook.

So it's not that privacy has disappeared among young people; it's that our expectations about it are changing. If there's an entire generation growing up that views a Snapchat comment as private, then that's the way the law should treat it. Just because we have the technology to eavesdrop on people โ€” whether online or in the street โ€” doesn't mean we should be allowed to use it as evidence in court. One might say the same thing about the unreasonable searches that the NSA was doing before Edward Snowden blew the whistle.


"We need to reconceptualize privacy, but that's hard," said Higgins. "We can expect that there might be a few more really terrible outcomes in the short and medium term before we understand that the old framework we had is legal, but not in line with norms and expectations. I hope we eventually get there."

Annalee Newitz is the editor-in-chief of io9, and this is her column. She's also the author of a book called Scatter, Adapt and Remember: How Humans Will Survive a Mass Extinction.