Ontario's Special Investigations Unit has found there are reasonable grounds to believe an Ottawa police officer committed a crime during the arrest and detention of Stacy Bonds.

Sgt. Steve Desjourdy was charged with sexual assault Tuesday morning. He has been assigned to administrative duties.

Desjourdy was caught on surveillance video stripping Bonds of her shirt and bra after she was forced to the ground in the Ottawa police holding cell in September 2008. He used a pair of scissors to cut off her clothes.

Bonds was left semi-clothed in a cell for more than three hours. Her lawyer says the incident left her sexually humiliated.

"What on earth is going on at the Ottawa Police Service," said lawyer Sean Dewart, who is representing Bonds in her $1.2-million lawsuit against the Ottawa Police Service.

Dewart says the charge against Desjourdy shows the police service needs to step up and address the issue of police abuse in cellblocks.

Ottawa Police Chief Vern White will not comment about the case because the matter is now before the courts. The SIU has also said it won't provide further comment.

Although police are sometimes charged for incidents that occur while on the job; it's unusual that a police officer would face a sexual assault charge stemming from an alleged incident that occurred in police headquarters.

"In my experience, it is rare that Ottawa police officers are charged with these serious types of offenses while they're in the course of their duties," said Ottawa criminal lawyer Cheryl Letourneau.

Bonds was arrested in downtown Ottawa for a liquor offence. Police allege she was in possession of open alcohol in a public place. She was later charged with assaulting a police officer.

However, those charges were thrown out by an Ottawa judge in October 2010 after he watched a video that showed how Bonds was treated by police. Justice Richard Lajoie referred to Bonds' treatment as an "indignity to a human being."

Following his ruling, the judge released the cellblock surveillance video to the media.

The footage shows Bonds being kneed in the back by Special Const. Melanie Morris. A group of officers then pins her to the ground before Desjourdy cuts off her clothes.

Bonds filed a lawsuit against the Ottawa Police Service in December; two months after her case was before the courts.

Her statement of claim argues the officers were vindictive and her poor treatment was influenced by her race. She also claims the incident caused her "emotional and physical trauma."

In a statement of defence, police allege Bonds was resistant during the search portion of the booking process.

The case was referred to the SIU for further investigation in November. Desjourdy was charged as a result of that investigation. He is scheduled to appear in court April 12.

The Ottawa Police Association, which has defended the police officers throughout the ordeal, says the organization will stick by Desjourdy during his court proceedings.

"In the interim, we'll be supporting our member through the process," said union president Steve Boucher.

Ontario Provincial Police are investigating the case as it relates to the Police Services Act. The provincial police will also look into the role civilian police officers played in Bonds' detainment.

The SIU is called in to investigate whenever police are involved in incidents resulting in death, serious injury or allegations of sexual assault.