(CBS) — As colleges gear up for a new school year, the Cook County Sheriff’s office is offering them guidance on how to deal with cases of rape on campus, reports WBBM’s Regine Schlesinger.

Initially, the sheriff’s office planned three training sessions, but demand was so overwhelming, staffers added a fourth.

Jan Russell who teaches the workshop, says too many colleges are sweeping sex assault allegations under the rug.

“When you un-found a case, because you want your numbers cleaned up, you actually are harming not only that case, potentially in the future where evidence may come up, but you’re stopping that investigation,” Russell said. “You may not be catching someone who’s a serial rapist.”

She says the key to getting to the bottom of what’s often a “he-said, she-said case,” is proper and thorough investigation.

Wayne Reynolds with the University of Chicago police says keeping an open mind is vital.

“Not to pre-judge, to listen, to evaluate and try to figure out a way how we can prevent things like that,” he said.

Heading into the new school year, colleges and universities are under a new federal mandate to do more to combat sexual assaults on campus.