PHILADELPHIA — A police chief's daughter accused of "slinging slurs" and throwing punches during a vicious group attack on a gay couple went on trial Thursday to fight felony charges.

Two co-defendants who pleaded guilty got probation — and were barred from downtown — but Kathryn Knott is fighting the charges.

The defendants were tracked down after images of the September 2014 attack were shared by news outlets and on social media. They were part of a group of suburban friends out on the town celebrating a birthday when they crossed paths with the couple on a side street. Profanity-laced taunts ensued, and before long, the couple were being punched and pummeled. One suffered a broken jaw and severe facial injuries.

Knott, 25, of Southampton, faces several years in prison if convicted of aggravated assault, conspiracy and other charges.

"She runs toward the fight," Assistant District Attorney Allison Ruth said. "Out of the 15 people out there that night, this defendant was slinging those slurs."

Knott's lawyer downplayed the supposed gay-bashing motive and said the dispute went bad when another woman was struck during the fray. He said his client never touched either victim.

The jury will hear about Knott's prior Twitter posts that derided gays. Ruth said they show "how she feels about gay people," but defense lawyer Louis Busico said they were posted years earlier, when his client was still in college.

The two co-defendants, Philip Williams and Kevin Harrington, both of Warrington, denied when they entered pleas that they were motivated by homophobia. They were ordered to volunteer at a community center for gays and lesbians as part of their sentence.

Knott lost her job at a hospital following her arrest. She remains free on bail.

The victims, Andrew Haught and Zachary Hesse, had been on their way for pizza when the attack occurred. They're expected to testify against Knott.