In the lawsuit, the office of DC’s attorney general alleged that Facebook’s privacy failings allowed users’ personal data to be harvested without their permission and later accessed by Cambridge Analytica.

Attorney general Karl Racine said in a statement: “Facebook failed to protect the privacy of its users and deceived them about who had access to their data and how it was used. 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 attorney general said 852 Facebook users in DC had downloaded the quiz app at the centre of the Cambridge Analytica allegations, and that 340,000 other DC residents could have been affected.

DC wants the social media company to establish protocols and safeguards to make it easier for people to control their privacy settings, and is also seeking restitution for consumers, penalties and costs.