During a court trial on Monday, the lawyer representing a Loudoun County teen that sexually assaulted a 15-year-old girl in the bathroom of Stone Bridge High School argued that the sexual assault was an "accident."

Attorney William Mann, the teenage boy's defendant, said in his opening statement that the encounter between the two teens was consensual, just the two previous occasions the meetings have occurred, according to The Washington Post.

"They discussed sex regularly," Mann said. "The encounter was just like it was before."

Although the defendant did not testify, prosecutors played interviews with the defendant and investigators in which he acknowledged "messing up."

The teen also noted that he did not intend to perform one sexual act with the girl, and stopped once he realized he was hurting her.

"The defendant initially told detectives the second sexual act did not occur, but later said it may have happened briefly and accidentally when a knee-length skirt he was wearing got caught on his watch as the pair were fumbling around in the bathroom stall," wrote The Washington Post.

The girl testified that leading up to the attack, the two had engaged in consensual sexual encounters with the defendant on two occasions in a girls' bathroom of the high school.

She said that her and the boy agreed to meetup in the bathroom at around 12:15 pm on the day of the assault.

"She testified they had not explicitly discussed having sex beforehand," The Washington Post wrote.

She said that she chose to go into the girls' bathroom because they was where they had usually met.

When the boy arrived, he met her in the handicapped stall and locked the door.

"The two talked, before the girl testified the boy began grabbing her neck and other parts of her body in a sexual manner. She testified she told her attacker she was not in the mood for sex, but he forced himself on her," The Washington Post wrote.

"He flipped me over," the girl stated. "I was on the ground and couldn't move and he sexually assaulted me."

She testified that the attack only ceased when someone came into the restrooms startling the boy. She noted that the second sexual act occurred a little bit later.

The judge ruled that there was sufficient evidence pointing to the defendant forcing the girl into two sex acts.

Sentencing for charges relating to the May incident will occur after a Loudon County Judge determines the outcome of the second set of sexual assault charges against the same teen stemming from an incident on October 6 at Broad Run High School.

On October 6, a female student was sexually assaulted after being forced into an empty classroom by the same student who had assaulted the girl at Stone Bridge High School.