Twitter completed the trifecta of social media kingpins standing against police surveillance yesterday when it joined Facebook and Instagram in restricting data available to Geofeedia, a social media analytics company.

The subject of a new report from the ACLU of Northern California, the tech outfit claims to have provided its location-based, social media trawling services to over 500 police departments already, but exactly which ones is not yet clear.

We do know, however, that the Chicago-based business is available for use in its hometown.

The Cook County Sheriff’s office recently released documents to MuckRock revealing that acquisition of the software was approved at the end of 2014. The materials were requested as part of an ongoing project with Color of Change on protester surveillance.

According to the release, the Department paid $12,000 for a 2015 subscription to the service and $13,500 for the current iteration.

Unfortunately, no policies for the use of the program were released in response to the request, despite specifically being mentioned. A follow up has been sent.

According to the release, the software was purchased using funds from the Department’s asset forfeiture program. The public recently got a closer look at asset forfeiture in the Windy City when the Chicago Reader, in collaboration with MuckRock and Lucy Parsons Lab, released a piece on the Chicago Police Department’s use of the controversial program, which has allowed police departments to seize materials they claim may have been involved or could help aid a crime; for the CPD, the program has netted over $47 million for agency use.

For more specifically on Geofeedia and social media surveillance check out Followed, our project with Little Sis.

Want to know if your local police department is using social media surveillance software? Enter your local agency into the Google Form below, and MuckRock will submit a request for free on your behalf.

Image by All-Nite Images via Wikimedia Commons and is licensed under CC BY 2.0