An employee of a homeless shelter in Oshawa has been charged with four counts of sexual assault, and Newstalk 1010 has learned that the centre has been receiving complaints "over the years."

Police say the suspect was a volunteer and staff member of Gate 3:16 from 1995 to 2012.

He had a number of roles, including teaching and counseling.

Recently, a number of women came forward to police, reporting allegations of sexual assault dating back to 15 years ago.

Former president of the shelter, Marten VanHarmelen, tells Newstalk 1010 the complaints are not new.

"Over the years, there have been a number of times that we got complaints," he says.

But he adds that their hands were tied because the complainants did not want to go to police.

"These homeless people and street people are very vulnerable and they get very nervous when it comes to making a statement to the police about something that has happened," VanHarmelen says.

Now that a number of victims have filed formal complaints with police and the accused has been charged, VanHarmelen says the employee has been fired.

When asked why the employee was not fired when the first complaints came in, VanHarmelen says because their hands were tied.

"You have to be careful with firing a person if you do not have sufficient proof," he says. "The experience is in the labour relations world that if you don't have proof enough then there is a good chance that they will get back at you, sue you, and all that."

VanHarmelen says everyone at the centre is upset about the case.

The centre will follow stricter rules now when hiring staff with a thorough background check.

"[We will] really, really go into their background."

67-year-old Earl Sanderson of Scugog Township has been charged wtih four counts of sexual assault.