After years of operating in a legal gray area, domestic drone use is starting to amass a number of official rules and guidelines. The US Justice Department is the latest to provide policy guidelines on the use of unmanned aerial vehicles (UAVs). On Friday it published its guidelines laying out how federal law enforcement agencies may (and may not) use the remote-controlled vehicles. So far, the FBI is the only agency within the department to use the drones in missions.

In a five page document, the department says that UAVs may not be used to monitor any activities protected by the First Amendment, such as peaceful protests and demonstrations. In addition, law enforcement must "seek a warrant in circumstances in which a person has a reasonable expectation of privacy," consistent with the Constitution.

Even in cases where the use of UAVs is allowed, it appears the Justice Department is keeping a close eye on the use of drones in the US. The guidelines say that the devices "may only be used in connection with properly authorized investigations and activities." And each agency will be responsible for maintaining detailed logs of all UAV missions.

The guidelines also call for yearly summaries to be submitted to the deputy attorney general for review. It also urges law enforcement to use the "least intrusive means to accomplish an operational need," suggesting that UAVs aren't right for all missions. In addition, among other rules, all pilots will have to be certified and information and documentation generated from UAV missions will have to adhere to existing privacy laws.

The Department of Justice's guidelines come just months after the FAA submitted its long-awaited rules for commercial drone use. The department says that its guidelines are consistent with those rules, which call for, among other things, certification and testing for private operators.