A PROSECUTOR launched into the start of Kathryn Knott's trial in the Center City gay-bashing case yesterday with these ugly words:

"You dirty f---ing faggot. Is that your f---ing boyfriend? F---ing faggot, f---ing faggot, f---ing faggot."

Standing before a Philadelphia Common Pleas jury, Assistant District Attorney Allison Ruth said in her opening statement that those slurs hurled by Knott and her friends on the night of Sept. 11, 2014 fueled a vicious, hateful attack on two gay men at 16th and Chancellor streets.

Knott didn't throw the worst of the punches - two guys in her group of about 15 people did - but "she runs toward the fight" and "she threw punches," Ruth said.

Defense attorney Louis Busico told the jury of eight women and four men in his opening statement that Knott, 25, of Southampton, Bucks County, was merely present when two men in her group got in a fight with the two gay men.

She didn't hit anyone, and didn't hurl slurs, he said.

"At no point in time will one of the [prosecution's] independent witnesses say she touched a soul," Busico said, adding that in videos taken that night, "you will not hear Kathryn say anything."

"The vile language, the faggot language, the f--- you language, none of it comes from her," he said, pointing to Knott, seated at the defense table in a white sweater, dark pants, and wearing glasses.

Knott, who is free on bail, is on trial on charges of aggravated assault, simple assault, recklessly endangering another person and conspiracy.

Two codefendants - Philip Williams, 25, of Warminster and Kevin Harrigan, 27, of Warrington, both in Bucks County - pleaded guilty in October and were sentenced to probation and community service. Only Knott took her case to trial.

Williams pleaded guilty to aggravated assault and conspiracy. Harrigan pleaded to simple assault and conspiracy.

Ruth said one of the victims, Andrew Haught, now 28, was injured so badly, his jaw was broken. A surgeon had to put screws into his jawbone to fix his face.

"His jaw was wired shut," she said, "like a medieval torture chamber for eight weeks," during which "he couldn't eat anything," and he lived on a liquid diet.

She said the videos - played to the jury yesterday - don't show the entire assault, and that evidence in the trial will also include antigay comments Knott had previously posted on Twitter.

"It goes to show her motive," Ruth said. "In this case, these tweets show how she thinks about gay people."

On the night of the attack, Knott was "slinging those slurs like it was nothing," Ruth said, contending that Knott is responsible for the victims' injuries - caused by Williams and Harrigan - under conspiracy and accomplice-liability law.

"Except for that hate, that energy, we wouldn't be here" at a trial, she contended.

Busico told jurors that the tweets "were made by a college student, four or five years ago," are distractions in the trial and are not related to what happened.

Later yesterday, Haught's boyfriend, Zachary Hesse, 29, testified that it was about 10:40 p.m. that night, when he and Haught were walking next to each other on Chancellor Street, a block south of Walnut, near Rittenhouse Square. They were going to get pizza at Broad and Locust streets.

As they approached 16th Street, Hesse said he heard a man say: "What is that, your f---ing boyfriend?"

Attorneys agreed the man who spoke to Hesse was Harrigan.

Asked by Assistant District Attorney Michael Barry how Harrigan's comment made him feel, Hesse testified: "I never had anybody speak to me like that. I was in shock." He said he thought to himself: "Who's saying this in the middle of Philadelphia?"

Hesse said he replied: "Yeah, what if it is my boyfriend? Do you have a problem with that?"

Harrigan shot back, "Oh, so you're a dirty f---ing faggot," Hesse testified. Hesse said he then took a few steps toward Harrigan and replied: "Maybe I am a f---ing faggot."

That's when Harrigan shoved him in the chest, said Hesse, who said he shoved Harrigan back. Harrigan then punched him in the face, Hesse said, as about six people, maybe more, in Harrigan's group "packed around me."

"It was a terrifying incident," Hesse said. "My arms were being held back."

The people in the group kept screaming "f---ing faggot" at him, Hesse said. He identified Knott, who was wearing a white dress that night, as one of the people yelling the degrading words.

Hesse demonstrated to jurors that Knott raised her hand in an open claw toward his face. He said he closed his eyes, expecting to get hit and was hit in the face.

Hesse said he was punched by multiple people that night and suffered multiple black eyes, but didn't need hospitalization.

Haught, however, was hit so hard in the head at one point that he toppled down to the ground, motionless. "I thought he was dead," Hesse said.

Haught, who spent five days at Hahnemann University Hospital, is expected to testify today before Judge Roxanne Covington.

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