"Because he was a teacher, because he was in a position of authority over the student, then that's the reason for the charge," said Bluffton Police Chief Nathan Huss.
Under Indiana law, it's legal for a teen to have a sexual relationship with an adult after they turn 16, except if the adult is in a position of authority, like a teacher.
"We have a really good working relationship with the bluffton police department," said Wayne Barker, Superintendent of Bluffton-Harrison Metropolitan school District.
Wayne says he first learned of the allegations on Friday morning when a student came forward to the Bluffton High School principal.
"I'm very encouraged that we had students come forward and speak very quickly about this from the time the alleged incident took place to the report being made," said Wayne.
The principal at Bluffton High School checked surveillance video, which showed Clark entering his classroom on Thursday morning followed by the girl who had been mentioned by the student.
In an interview with police, the girl said she was only sexual with Clark after she turned 18. When police interviewed Clark, he admitted to having a sexual relationship with the girl back in June when she was still 17. Clark resigned from his teaching and extracurricular positions at the high school.
"We're covering his classes right now with our present mathematics staff that we have at the high school and we have a sub as well. And we posted a position for a math teacher," said Wayne.
Joshua Clark's been charged with one count of child seduction, which is a class C felony. He turned himself in Tuesday night but then bonded out.
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