A new bill would give the federal government the legal authority to shoot down drones that are deemed “credible threats” to national security. The problem – say critics – is that the bill doesn't define credible threats or specify target areas. It may also allow the federal government to sidestep laws requiring authorities to get courts for permission to conduct surveillance.

The drone provision, part of a massive FAA Reauthorization Bill, would let FBI and Department of Homeland Security (DHS) personnel to shoot down or seize suspicious drones flying inside the U.S. Agents would also be able to hack into drones and change their flight path.

The increasingly popular aircraft have found legitimate uses among wedding photographers, bridge inspectors and retailers who need packages delivered. They’ve also been used to drop contraband drugs and weapons into prison yards, interfere with first responders (in particular, firefighting planes) and violate the privacy of citizens who have a reasonable expectation of privacy. A recent Newsweek article highlights the terrorism potential of drones: “Terrorist Drone Attacks Are Not an ‘If’ But ‘When.’.

DHS Secretary Kirstjen Nielsen says terrorists and criminals could use drones to drop explosive payloads, deliver harmful substances, disrupt communications, and conduct illicit surveillance. "The threat is real.”

The measure would allow Nielsen and Attorney General Jeff Sessions, in coordination with Transportation Secretary Elaine Chao, to determine "credible threats," against a "covered facility or asset" that shows a "high risk and potential target for unmanned aircraft activity."

However, the American Civil Liberties Union (ACLU), however, says a provision that would permit federal authorities to monitor and track the unmanned aircraft without prior consent - contrary to current wiretap laws – could be used against journalists. The ACLU argues that the provisions give the government the ability to surveil, seize or shoot down a drone without due process – something that could hinder press freedom.

There are now more than a million drones registered with the FAA.