PITTSBURGH (KDKA/AP) – A Plum Area School District teacher accused of having sex with a student will stand trial.

Jason Cooper, 38, was ordered to stand trial on all counts Wednesday morning.

Cooper was arrested back in February on charges that he had an inappropriate sexual relationship with an 18-year-old female student.

Today, the alleged victim, a 12th grader, testified that their sexual relationship began after she turned 18.

During testimony the girl said, “When I was a sophomore, I used to sit in his room during study halls. We became involved early this year. We had a kiss in his classroom. We went on with our relationship. We had sex.”

Sex between a teacher and an adult student is illegal in Pennsylvania, because the student isn’t considered legally able to consent given the student-teacher relationship.

Cooper was charged with institutional sexual assault, corruption of minors and furnishing alcohol to a minor.

The defense still argues There’s a difference between losing his teaching license for the relationship and being convicted of a crime.

“They should lose their license. It’s inappropriate and it’s wrong, but it’s not criminal. There’s a big distinction between moral and criminal. I don’t think it’s criminal and that’s what I’m hired to do. Mr. Cooper has surrendered his certificate to teach and these relationships require that. So, there are consequences, but the criminal consequences do not apply,” defense attorney Mike DeRiso said.

The encounters allegedly took place at both the high school and at Cooper’s home.

Cooper was previously ordered to not have contact with the alleged victim after his initial arrest. However, he was arrested a second time for allegedly contacting the student and discussing the case.

Documents say Cooper decided to pick up the phone in February and call an 18-year-old senior that he reportedly had sex with.

Cooper allegedly had a 30-minute conversation with the teen, during which they talked about her pending testimony in the case.

The girl’s father called police, told them about the phone call and Cooper turned himself in.

An addition charge of intimidating a witness or victim was added at that time.

He also allegedly tried to contact a 17-year-old friend of the victim via a Facebook request, which she rejected. He also allegedly then sent her a text message saying “hey.”

Cooper was later ordered to house arrest without Internet access.

Cooper’s attorney says his client didn’t break the law because his alleged victim is 18.

“Once an individual turns 18 there is no legislation that exists to restrict the actions of an adult and who and what they can do behind closed doors,” DeRiso said.

But District Judge Linda Zucco ruled a Common Pleas Court judge or jury will have to decide that question. She found there was enough evidence to hold Cooper for trial on all charges.

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