The FBI began experimenting with drones in 1995, but didn't view them as a viable option for video surveillance until a full decade later. Since then, however, the agency appears to have slowly but steadily moved forward in building its drone program. Now, details of that program have been revealed in a series of recently released documents sentI to Citizens for Responsibility and Ethics in Washington (CREW), an advocacy group that issued a Freedom of Information Act request in June. Though CREW was interested in learning what company provided the FBI's drones and where the purchases' funding came from, that information is largely redacted. Even so, the documents do reveal quite a bit about the program's development, including how the FBI has been using drones and what it plans to do with them in the future.

The FBI says there are no constitutional issues with its current use of drones

The documents show that the FBI's first operational drone deployment was in October, 2006. Drone use was "limited over the next four years," the documents read, noting that funding issues and compliance with Federal Aviation Administration (FAA) regulations were major limiting factors. While the FBI's Technical Response Unit oversaw its drone program at first, the program was transferred to its Video Surveillance Unit in 2009, at which point drone "inventory and missions began to increase." The documents suggest that this wasn't so much a matter of the new unit utilizing them more, but that agents began to better understand what drones were capable of.

The documents don't reveal how many times drones have been used, but in a letter to Rand Paul this July, the government said that the FBI only used them 10 times for surveillance missions. As these documents show, such surveillance and search missions are among the FBI's primary uses of drones. In particular, the FBI notes that they're useful for missions where "unique" requirements would prohibit sending in a manned aircraft.

The agency doesn't go into detail about when it authorizes the use of drones, but it does claim that "there are neither constitutional nor statutory prohibitions" to its current operational drone use. Details on when they can be used appear to have been written but redacted from this release, but the documents do suggest that the FBI largely applies the same rules to drones as it does to manned aerial surveillance.

FAA regulations have been a continual hurdle

While drone use appears to be increasing, funding deficits and FAA regulations continue to be major hurdles. The FBI's drone program doesn't receive discrete funding, but comes instead out of the Video Surveillance Unit. Annual expenditures on drones have been redacted from the documents, but one partially censored email suggests that its purchasing budget may have been "cut to zero" for 2013.

The drone program also seems to receive little in the way of special treatment from the FAA. The documents frequently cite difficulty complying with FAA regulations as a holdup for the program, with its inability to comply with a regulation known as "See and Avoid" being a particular issue. Under See and Avoid, aircraft operators must maintain "vigilance" with regard to seeing and avoiding other aircraft — something that's difficult to do when remotely piloting a drone. The FBI notes that it's been working with the FAA to mitigate these concerns and to set up a nationwide approval system allowing it to more easily deploy drones.

As of 2011, the FBI said that it was interesting in deploying more unmanned aerial systems across the agency, but the actual number of drones it's acquired appears to have been redacted from the documents — it was also working on developing a pilot training program that year. In 2012, the FBI wrote that it planned to continue using drones for search and surveillance, and that it could also employ them in other scenarios, such as assisting SWAT missions. The drone program is clearly still growing at the FBI, but while the agency may have identified plenty of uses for it, recurring troubles appear to be keeping it from getting far off the ground.

CREW has posted the series of FBI documents online for others to read through, some of which have been declassified. According to Motherboard, this is only the first batch of files, and more may be on the way. A Washington, DC district court reportedly directed the FBI to release drone documents to CREW on a rolling basis, suggesting that more will come as the program advances. CREW also reportedly intends to appeal the current batch of documents' heavy censoring, potentially revealing even more detail about the program's development.