Though Mr. McInnes has said he disavows racism, he wrote that the prominent white nationalist Richard B. Spencer comes across as perfectly reasonable in conversation, and he said Senator Cory Booker of New Jersey, who is black, is kind of like Sambo. When he quit the group, he blamed rumors and lies and terrible journalism for undermining the greatest fraternal organization in the world.
This whole idea of white nationalists and white supremacy is a crock, he added. Such people dont exist.
At the same time, previously unreleased video obtained by The New York Times shows that the Proud Boys initiated the attack in Manhattan against a handful of anti-fascist protesters, not the other way around, as Mr. McInnes had initially said.
Prosecutors said at court appearances for some of the accused Proud Boys members that video evidence will prove that the Proud Boys started the fight.
Asked about the Proud Boys, John Miller, deputy police commissioner for intelligence and counterterrorism, confirmed that incidents like this make it more likely that theyll be higher on the radar.
Enrique Tarrio, chairman of the administrative chapter of the Proud Boys, maintained that the group repudiates hate and racism and pointed out it has ordered white supremacists to leave its events in the past.
The violence started on Oct. 12 shortly after Mr. McInnes gave a speech at the Metropolitan Republican Club on East 83rd Street, a bastion of establishment conservatism.
Outside a crowd of left-wing protesters chanted No Nazis, No KKK, No fascist U.S.A. After the event, the police kept the attendees and protesters separate, but a handful of leftists, wearing masks, circled the block and tried to intercept the Proud Boys on East 82d Street, the police said.
The security video from a nearby building shows that at 8:19 p.m. two men in Proud Boys shirts, Maxwell Hare and Geoffrey Young, strode briskly east from Park Avenue on 82nd Street toward about six protesters some 100 feet away.
Then, Mr. Hare charged the leftists, and a protester threw a plastic water bottle, which sailed past him, the video shows. Mr. Hare crashed into one of the protesters, hurling punches.
Just before he charged, another video filmed by a freelance videographer recorded that someone yelled: Proud Boys! You ready? Proud Boys!
Within seconds more men rushed down the block from Park Avenue and joined the fray, the two videos show. The brawl lasted about 60 seconds.
A third video filmed by a man who was with the Proud Boys showed Mr. Hare and others after the fight exulting about smashing the head of a foreigner.
Both Mr. Young and Mr. Hare have pleaded not guilty and claim through their lawyers they were attacked.
One challenge facing prosecutors is that the victims of the attack have refused to cooperate with the authorities, which means the case will rely heavily on videos from security cameras and onlookers.
The indictment refers to the victims as Shaved Head, Pony Tail, Khaki and Spiky Belt.
The identity of these Antifa members remains unknown, Joshua Steinglass, an assistant district attorney, told a judge at an arraignment for seven of the defendants on Dec. 14.