NYPD Detective Vincent Cheung has announced that he is suing a protester who was caught on video hurling racist, anti-Asian insults at him during a protest in March.

In a video of the confrontation released by the police, the protester, Terrell Harper, was just feet from Cheung’s face as he cursed at him, punctuating his comments with racist stereotypes mocking Cheung, who is Chinese American, Yahoo reports.

The lawsuit, filed in Manhattan Supreme Court Tuesday, says Terrell Harper harassed him repeatedly during a demonstration on March 11, calling the cop a “goddamn cat eater” and asking if “he can see right?”

“You going to Judo chop me? I don’t give a f–k, you are being recorded, too,” according to a disturbing video released by the Detectives Endowment Association, which filed the suit on behalf of Detective Vincent Cheung, the New York Post reports.

In the moment, Cheung made no move to apprehend Harper, who is black. Harper said after the protest he returned home to Asbury Park, New Jersey, after the protest, which he said was a weekly demonstration for transgender rights and “in solidarity with end Asian hate.”

At the news conference last week, at the headquarters of his union, the Detectives Endowment Association, Cheung said he had often encountered verbal abuse before, but that he was surprised that during a demonstration for racial justice and equality, Harper had gone on what he called “an anti-Asian beratement for over 15 minutes.”

The lawsuit says that Cheung suffered severe emotional distress and was permanently and seriously injured by Harper’s conduct, which, it said, had incapacitated him from his usual duties and required him to seek medical attention. It asked that the court compel Harper to pay unspecified monetary damages.

Lawyers who observe police action closely said that they could not recall a lawsuit of this type — pursuing monetary damages from a protester for language used at a demonstration — and added that even if the suit is wholly unsuccessful, it could still represent a new way for the police to confront protesters. A lawyer representing Cheung said that the police believe that civil court is “the only remedy with which they are left.”

“Many officers have said they wouldn’t hesitate to seek that remedy, not with the expectation of a financial windfall, but hopefully as a deterrent to such uncivilized and dangerous behavior,” said the lawyer, James M. Moschella.

In interviews with the New York Times, Harper, 39, apologized for what he acknowledged were racist comments. He said the video had been taken out of context, and that he typically uses racist remarks as part of a broader explanatory monologue to demonstrate what racism looks and feels like.