The legality of drone surveillance is vague. But one thing is clear: the feds are using them, and we've just learned from a letter from the FBI Senator Rand Paul, they've used them without warrants in the US in at least 10 different cases.
The FBI's assistant director for the office of congressional affairs Stephen D. Kelly writes:
Since late 2006, the FBI has conducted surveillance using UAVs in eight criminal cases and two national security cases... None of the UAVs used by the FBI are armed with either lethal or non-lethal weapons, and the FBI has no plans to use weapons with UAVs. The FBI does not use UAVs to conduct "bulk" surveillance or conduct general surveillance not related to an investigation or assessment.
Kelly goes on to say that drone surveillance, even without a warrant, must be approved by "senior FBI management at FBI headquarters and in the relevant FBI field office." He cites the FBI's use of a drone in helping rescue a kidnapped Alabama five-year-old earlier this year as a successful example. He also mentions that three other cases in which the FBI was approved to do warrantless UAV monitoring, but did not.
What's more, Kelly says the FBI hasn't actually sought warrants for any of the cases where UAVs are used. And while he claims that the FBI is well within its Fourth Amendment rights to do so, it's still cause for concern. We don't know how often or how extensively the FBI is using drones. And the agency has declined to offer more details on the matter. [Rand Paul via The Verge]