A long-time University of South Dakota history professor resigned in the middle of the academic year amid allegations he had a sexual relationship with a married student.
The university is staying tight-lipped, but in court documents, the student's husband revealed the affair with Dr. Robert Hilderbrand late last year.
For 35 years, Dr. Robert Hilderbrand was a well-known history professor at USD.
In court documents obtained from the Clay County Clerk of Courts, Hilderbrand was served a subpoena on November 6, 2012 to testify in a divorce filing between David Cowles and his wife Sara Cowles, a USD undergraduate.
In the sworn affidavit, David Cowles says he discovered his wife of nearly nine years, was having an affair with Hilderbrand, who was her professor at the time.
David Cowles says he has copies of email exchanges, which "explicitly show the existence of their affair."
The alleged affair goes against the South Dakota Board of Regents policy which states that university faculty members are not allowed to have consensual sexual relationship with any student "under their academic supervision."
Hilderbrand resigned before the start of the current semester. And the university's media relations office wouldn't comment on the resignation, saying it was a personnel issue.
But Director Phillip Carter did say Hilderbrand was already scheduled to retire at the end of the spring semester.
And news of the alleged affair is catching some students off guard.
"It's pretty scary, too I guess. But I don't know, it's just really shocking," freshman Emily Spaid said.
Repeated attempts to contact Hilderbrand on Thursday were unsuccessful.
USD officials also would not comment on how the school rescheduled the professor's classes this semester, after his sudden resignation.