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The American Civil Liberties Union and protesters from Maryland and Washington, D.C., filed a lawsuit on Thursday against the Trump administration over the use of force to push peaceful demonstrators out of Lafayette Square on Monday.

President Trump, Attorney General William Barr, and other federal officials are named as defendants in the lawsuit. Security personnel used tear gas and rubber bullets to disperse the crowd, which was protesting the death of George Floyd. This happened shortly before Trump walked over to take photos in front of St. John's Church.

The lawsuit states federal forces had "no legitimate basis to destroy the peaceful gathering," and this case is about Trump and Barr "ordering the use of violence against peaceful demonstrators who were speaking out against discriminatory police brutality targeted at black people."

Barr, who has been leading the federal response to the protests, on Thursday defended the use of force, saying protesters were becoming "unruly." Several military leaders have in turn denounced it, with former Defense Secretary James Mattis, a retired Marine general, calling the show of force an "abuse of executive authority," adding that "we must reject and hold accountable those in office who would make a mockery of our Constitution."