Ontario's Special Investigations Unit has cleared a South Simcoe police officer of any wrongdoing in a September arrest in Innisfil that left a 46-year-old man with a broken ankle.

SIU director Joseph Martino concluded there are "no reasonable grounds" to believe the officer committed a criminal offence, writing in his Jan. 13 report that "there is no basis for proceeding with criminal charges in this case" and that "the file is closed."

The incident began at about 8:45 p.m. on Sept. 17, when South Simcoe police received a 911 call reporting that a man had punched a woman in the face, according to the SIU report. The caller said the man had been drinking whiskey, was impaired, was threatening the caller, and was trying to leave the property on a motorcycle.

Officers were sent to a residence in Innisfil's north end, in the area of Big Bay Point Road and Yonge Street, to investigate what police described as a case of intimate partner violence.

When officers arrived, they spoke with the woman, but the man had already left on a 2007 Suzuki Boulevard motorcycle with no licence plate. Police allege he was intoxicated at the time.

While officers were still speaking with the woman, the man returned to the area — then turned his motorcycle around and rode off again. Officers followed and activated their cruiser's emergency lights.

Seconds into the pursuit, the cruiser pulled up alongside the motorcycle, which had come to a stop with its engine still running. An officer got out of the cruiser and pushed the man on the right upper torso, causing him to topple to his left with the motorcycle landing on top of him.

The man was handcuffed without incident but was taken to hospital, where he was found to have a fractured left ankle.

In his report, Martino acknowledged the injury was caused by the officer's physical force, but concluded the contact was justified.

With information at his disposal that the complainant had assaulted the (woman) and operated a motorcycle while inebriated, I am satisfied that the (officer) was within his rights in moving to arrest him for assault and impaired operation of a motor vehicle,

Martino also found the push itself was proportionate to the situation, according to the SIU report.

Though the complainant was stopped by the side of the road, he was still atop his motorcycle with the motor running and in a position to quickly put the vehicle back in motion. Given his erratic and violent behaviour to that point, the (officer) would rightly have been concerned that the complainant might well do so, endangering himself and others given his current condition.

The officer declined to be interviewed and did not provide his notes, which is his legal right under SIU rules.

The SIU is an independent government agency that investigates incidents involving police that result in death, serious injury, sexual assault or the discharge of a firearm at a person. Its civilian investigators determine whether officers committed a criminal offence; depending on the evidence, charges may be laid or the case closed.

Martino's full report is available at siu.on.ca.