The two police officers suspended after video emerged of them shoving a 75-year-old man to the ground were charged on Saturday.
In a virtual arraignment at Buffalo’s city courthouse before Judge Craig Hannah, officers Robert McCabe and Aaron Torgalski were charged with second-degree assault.
They entered not guilty pleas and are scheduled to return on 20 July for a felony hearing. They were released on their own recognisance without bail.
Both officers were suspended from duty without pay after the incident on Thursday in Niagara Square, Buffalo during a protest over the death of George Floyd, a black man who was killed in police custody in Minneapolis last month.
The police emergency response team had been told to clear protesters from the area outside the city hall once a curfew came into effect.
Protester Martin Gugino, 75, struck his head on the sidewalk when he fell after being pushed. Video showed blood pooling around his head. He is currently recovering in hospital.
All 57 members of the team resigned in protest at the officers’ suspension, but remain part of the overall police force.
Text messages seen by a local TV station asked fellow officers to show their support outside the courthouse on Saturday.
Hundreds of law enforcement and firefighters gathered outside the building and shielded the two officers from news crews with an umbrella and a sheet as they entered from a holding area.
After the officers had been charged, the crowd cheered loudly as they exited the courthouse before dispersing.
— Katherine Chloé Cahoon (@KatChloeCahoon)June 6, 2020
Erie County district attorney John Flynn, speaking after the arraignment, said that on both sides, police and protesters, the overwhelming majority are peaceful across the nation but that you will always have individuals who will cross the line.
Mr Flynn denied he was choosing sides by prosecuting the two officers. The case will be handed to a grand jury to consider whether there was intent to cause physical injury.
The mayor of Buffalo has said that the elderly protester was an “agitator” who has been asked to leave the area “numerous” times.
Byron Brown said that Mr Gugino, was trying to “spark up the crowd of people”.
Mayor Brown also said that he would not fire the two officers until an investigation had played out, despite calls from the community and New York Governor Andrew Cuomo.
Protests on Friday in Buffalo were peaceful. More are expected today.