Stephen Lam / Reuters

Facebook and Instagram developers are no longer allowed to siphon information about you from public posts and package that information into surveillance tools for law enforcement, Facebook announced Monday.

The social networking giant updated its policy, clarifying that developers can't “use data obtained from us to provide tools that are used for surveillance.” Facebook said the new policy now makes the ban on surveillance tools explicit. "Over the past several months we have taken enforcement action against developers who created and marketed tools meant for surveillance, in violation of our existing policies; we want to be sure everyone understands the underlying policy and how to comply," Facebook said.

The announcement follows a widely discussed American Civil Liberties Union investigation last year that uncovered a partnership between law enforcement officials across the country and a social media monitoring company called Geofeedia. Through public records requests, the ACLU learned that Geofeedia had been providing law enforcement with information gathered from social media, including people's location data. Geofeedia, which works with hundreds of local police departments, also specifically targeted people on Facebook, Instagram, and Twitter who had participated in demonstrations against police violence and abuse, the ACLU found.

The investigation raised serious concerns about Twitter and Facebook's role in aiding government surveillance, and it undercut the companies' public commitments to supporting activism and free speech. Since the results of the ACLU's investigation went public, Facebook, Instagram, and Twitter have cut off Geofeedia's access to their users' data.

The ACLU praised Facebook's updated developer policy as a positive change. “Now more than ever, we expect companies to slam shut any surveillance side doors and make sure nobody can use their platforms to target people of color and activists,” said Nicole Ozer, the director of technology and civil liberties at the ACLU of California, in a statement.

Still, the ACLU, the Center for Media Justice, and Color of Change have urged Facebook to do more to enforce their prohibition on surveillance. In a statement Monday, the advocacy groups described the updated policy as a "first step."

Facebook enforces its developer rules through both automated and human audits. The company told BuzzFeed News that developers must disclose what they are using Facebook data for, and that Facebook can conduct broader audits after they receive a complaint of potential violations. But the advocacy groups emphasized the need for strict enforcement of Facebook's policies to suss out developers who break surveillance rules, and "swift action for violations."