Prisons have a drone problem. In August, a drug-carrying drone was caught ferrying half a pound of various drugs into Ohio's Mansfield Correctional Facility, sparking a full-blown fight when it landed in the yard. A year earlier, a similar landing took place at a maximum security prison in South Carolina, followed by another in Australia. At the same time, French officials struggled with a rash of unexplained flights near nuclear plants, suggesting the threat isn't limited to prisons.

It's a classic technological imbalance: for a few hundred dollars, anyone can buy a machine capable of out-flying most of the security measures in place at an open-air facility. The FAA's drone registration proposal may even the odds a little, but law enforcement agencies are still surprisingly out-gunned if they need to take down a hostile drone. Short of shooting it down, what can a police officer or prison guard do?

As the world's biggest police suppliers gathered at the International Association of Chiefs of Police (IACP) conference this week, solutions were surprisingly hard to come by. The best anti-drone weapon at the show was Battelle's Drone Defender, best known from a video that tore through YouTube last week. Set for release in 2016, the Drone Defender is essentially a radio jammer built on the frame of an assault rifle. When the trigger is pulled, the Defender floods its target with overwhelming signals on all the frequencies used by commercial drones, including GPS, cutting it off from the pilot. Without any readable signal from a controller, the drone will automatically hover to the ground. "We wanted something that was safe, effective, and non-damaging so you can still do forensics afterwards," said Alex Morrow, the project's technical director.

But while the system works, it's already running into a legal barriers. The broadest problem comes from the FAA: for the time being, drones are classified as aircraft, and it's a federal offense for anyone to interfere with the operation of an aircraft in mid-flight — even police. The FAA is still new to the business of regulating drones, and many are expecting some kind of carveout that distinguishes lightweight drones from 2-ton airplanes, making the concerns more theoretical than practical. Battelle says in private conversations, the FAA has been positive toward the device. Still, the aviation issues have been enough to scare many companies away from the category.

The jamming itself is also illegal, presenting an even trickier legal problem. The FCC has a blanket ban on jamming devices, and there's no carveout expected for anti-drone technology. Federal agencies can get around the provision, since they report to the NTIA rather than the FCC, but the rule cuts out the vast majority of law enforcement, including state prisons like Mansfield. It also means that when the Drone Defender goes on sale to law enforcement next year, it will reach only a fraction of the agencies that might use it.

The alternatives to jamming are both more expensive and more elaborate. A UK company called Selex was also present at IACP, offering a system it calls Falcon Guard, which launched last month. The system locates drones through a combination of conventional methods, including radar, electronic radiation, or infrared cameras. Once the drone is located, Falcon hijacks the video feed rather than jamming its circuits, allowing organizers to open up a direct channel to whoever's operating the drone. They can still shoot down the drone if necessary, but Selex thinks the additional warning will help scare off low-level mischief makers. "I have a fear that someone targets an NCAA football game as a prank, drops a stink bomb or flour and it causes public hysteria," says James Olson, Selex's director of advanced systems like Falcon.

A map prepared by Cunning Running LTD in advance of the Brittania launch

The cheaper alternative is to stop drones from lifting off in the first place. When Queen Elizabeth christened the Brittania this summer, UK police preemptively cleared out areas where a paparazzi drone operator might set up, using analytics from a local company called Cunning Running Ltd. Since operators need a line of sight, analysts were able to provide a limited space to clear.

Still, that tactic won't help in situations like Mansfield where the threat is effectively indefinite. In those cases, law enforcement is left waiting for a technical or regulatory fix that may not be coming any time soon. In the meantime, drone pilots will have a serious technical advantage over anyone who wants to take one down.

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