GILBERT, Ariz. -- An instructor with the Army Junior Reserve Officer Training Corps (JROTC) program at Highland High School is accused of sexual conduct with a minor.
Police said Joseph Stephenson, 41, allegedly had a sexual relationship with a 15-year-old female student.
Stephenson is facing a charge of sexual conduct with a minor.
Police said they found out about the relationship on Sunday from the girl's family. She had confided in her sister who then told their parents.
He started working at the school in Aug. 2013 and only taught ROTC, according to a spokesperson for the district.
"He seems like he's really serious all the time, doesn't seem like he'd do anything like this," said Highland High Senior Diana Schmidt who knows of the teacher.
"I think our teachers should be focused on teaching us and not getting involved with students," said Schmidt.
Police told 3TV it's not believed any other students were involved, but they're still investigating the case.
Stephenson has been placed on administrative leave, according to the district.