The top legal officer in the US capital city has sued Facebook over privacy violations related to personal data leaked to the Cambridge Analytica consultancy working on Donald Trump's 2016 campaign.
The lawsuit by the District of Columbia attorney general is likely the first by an official US body that could impose consequences on the leading social network for the data misuse.
"Facebook failed to protect the privacy of its users and deceived them about who had access to their data and how it was used," said Attorney General Karl Racine in a statement.
"Facebook put users at risk of manipulation by allowing companies like Cambridge Analytica and other third-party applications to collect personal data without users' permission. Today's lawsuit is about making Facebook live up to its promise to protect its users' privacy."
The lawsuit filed in the DC Superior Court seeks an injunction "to ensure Facebook puts in place protocols and safeguards to monitor users' data and to make it easier for users to control their privacy settings," and "restitution" for consumers.
There was no immediate comment from Facebook.
Facebook has admitted that up to 87 million users may have had their data hijacked by Cambridge Analytica, which shut down weeks after the news emerged on its handling of private user information.
A "whistleblower" at the consultancy said it used Facebook data to develop profiles of users who were targeted with personalized messages that could have played on their fears.
The scandal has triggered a series of investigations and broad review by Facebook on how it shares user data with third parties.
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