Philadelphia District Attorney Larry Krasner said Graf was identified with the help of video and photographic evidence, as well as eyewitness interviews.
“This is someone who frankly has a violent record in two different counties and has shown during his life a willingness to be involved in the serious injuring of people,” said Krasner.
In 2005, Graf pleaded guilty to simple assault in Philadelphia. He was convicted of the same charge in connection to a 2007 incident in Bucks County.
Fishtown resident Matthew Williams was also attacked on June 1.
He said one of the men threw him off his bike, then kicked and punched him in the face before threatening him with a bat while he and others loomed over him as he lay on the ground, bleeding.
Williams said he was approached after being separated from his girlfriend, who stopped her bike after one of the men tried to hit the couple with full water bottles. This after they mistakenly thought the group was part of the Justice for George Floyd protests, and raised their fists in solidarity.
The couple has given statements to prosecutors about the alleged attack. No charges have been filed yet.
Krasner on Thursday did not rule out the possibility of more arrests in connection to the vigilante gathering in Fishtown.
“Anyone who was out there assaulting people should be worried,” he said.
Mayor Jim Kenney has said it was a “mistake” for police to tolerate the group for as long as they did.
During the same news conference, Police Commissioner Danielle Outlaw said her department does not “endorse or condone any form of vigilante justice,” adding that it did not ask the group for protection that night.
“I didn’t ask them to do that. I don’t welcome that. I don’t invite them to come back. And we don’t need them, said Outlaw.