Facebook has been sent a subpoena by police in Washington D.C, which will compel the social media platform to give authorities data on several protesters who were challenging Trump’s presidency in January.

According to CityLab, the subpoena from the U.S Attorney’s Office for the District of Columbia was issued January 27. The document is signed by the Washington D.C police department. As Mashable reports, over 200 people were arrested – including media and law observers – during the demonstrations. Benjamin Carraway, a defence attorney, filed a class-action lawsuit against the police, stating that officers had used unnecessary actions against the largely peaceful protesters. Allegedly unconstitutional tactics were used, like confining protesters by 'kettling' and spraying chemicals to control crowds.

“Around the time of Trump’s swearing in, John Doe MPD Officers and John Doe Park Police officers surrounded individuals who were at or near 12th & L St., NW... without warning and without any dispersal order, the police officers kettled all of the plaintiffs,” the complaint said. “Defendants included in the kettle not only protesters who had engaged in no criminal conduct, but also members of the media, attorneys, legal observers, and medics... defendants proceeded to indiscriminately and repeatedly deploy chemical irritants, attack the individuals with batons, and throw flash-bang grenades at the kettled individuals.”

The mass arrests also saw authorities keep protesters’ phones. With many charged with felony rioting, reports allege that phones were picked for evidence. As Citylab previously reported, an arrested person marked as a medic noticed activity on his Gmail account when it was in police possession. Now, the police want additional information from a direct source like Facebook with the subpoena. Authorities have previously asked social media networks and messaging sites, like Facebook and Facebook-owned Whatsapp, to snoop on messages. Monitoring sites like Media Sonar, Geofeedia and Digital Stakeout have also been utilised to keep track of people in real time, uncovered by the ACLU.

The police can’t comment on the subpoena, and Facebook also can’t comment on individual cases. However, as Mashable notes, Facebook’s law enforcement guidelines shed a bit of light:

“A valid subpoena issued in connection with an official crime investigation is required to compel the disclosure of basic subscriber records. Those records may include: name, length of service, credit card information, email address(es), and a recent login/logout IP address(es), if available.”