Why This N.Y.P.D. Detective Is Suing a Protester In an unusual move, Detective Vincent Cheung is suing a man who hurled racist insults at him. The lawsuit raises thorny questions about free speech. Protesters who filled the streets after George Floyd’s murder last May were at times met with violent treatment by the police. The police say some protesters were verbally abusive.Credit...Gabriela Bhaskar for The New York Times April 29, 2021 When demonstrations against racism and brutality in policing filled New York’s streets last summer, the police confronted protesters with tactics so aggressive and at times violent that a remorseful Mayor Bill de Blasio later issued a public apology.