The Justice Department says that department personnel "may never use UAS [unmanned aircraft systems, or drones] solely for the purpose of monitoring activities protected by the First Amendment or the lawful exercise of other rights secured by the Constitution and laws of the United States."
That came in guidelines issued for use by law enforcement as a tool to help with things like "kidnapping investigations, search and rescue operations, drug interdictions, and fugitive investigations."
Use must also square with the Fourth Amendment prohibition on unreasonable searches and seizures.
DOJ said that personally identifiable information (PII) collected in an authorized operation cannot be retained for more than 180 days, subject to what sounds like a fairly liberal carveout if it is "necessary for an authorized purpose."
To employ a drone, law enforcement must get approval "(1) at the Assistant Special Agent in Charge-or-equivalent level at the relevant field office, and (2) by an executive level supervisor within the agency's aviation support unit or a designated executive level supervisor at the agency's headquarters."
On the transparency front, DOJ said that it will provide updates of the drone guidelines on its website and, without giving away any info that might compromise ongoing operations, will provide a "general summary" of UAS operations annually.