On Tuesday, the American Civil Liberties Union (ACLU) of California announced that, after the organization obtained revealing documents through public records access requests, Facebook and Instagram have cut off data access to a company that sells surveillance products for law enforcement. Twitter has also curbed the surveillance product's access.

The product, called Geofeedia, is used by law enforcement to monitor social media on a large scale, and relies on social media sites' APIs or other means of access. According to one internal email between a Geofeedia representative and police, the company claimed their product "covered Ferguson/Mike Brown nationally with great success," in reference to to the fatal police shooting of a black teenager in Missouri in 2014, and subsequent protests.

"Our location-based intelligence platform enables hundreds of organizations around the world to predict, analyze, and act based on real-time social media signals," the company's website reads.

According to the ACLU, Instagram provided Geofeedia access to its API; Facebook gave access to a data feed called the Topic Feed API, which presents users with a ranked list of public posts; and Twitter provided Geofeedia, through an intermediary, with searchable access to its database of public tweets. Instagram and Facebook terminated Geofeedia's access on September 19, and Twitter announced on Tuesday that it had suspended Geofeedia's commercial access to Twitter data.

Geofeedia did not immediately respond to Motherboard's request for comment.

Social media monitoring software has become an attractive tool, and controversial issue, for law enforcement. ACLU's concern, according to the group's blog post, is that Geofeedia's technology could be used to target neighborhoods of where people of colour live, or monitor activists.

In May, Denver police spent $30,000 on Geofeedia,The Daily Dot recently reported.

This isn't the first time social media giants have taken issue with surveillance companies using its platforms. In May, Twitter cut off access to Dataminr, a service which attempts to identify unfolding events or political unrest.

But the ACLU says there is more to be done, particularly when it comes to the social media networks themselves.

"Beyond the agreements with Geofeedia, we are concerned about a lack of robust or properly enforced anti-surveillance policies. Neither Facebook nor Instagram has a public policy specifically prohibiting developers from exploiting user data for surveillance purposes," the group writes. In response, the ACLU is calling for no data access to be given to developers of surveillance tools; for companies to publish transparent policies around their data being used for surveillance, and for greater oversight of developers.

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