A Cape Breton police officer has resigned after being convicted and sentenced to three months of house arrest with conditions for obstruction of justice and breach of trust.

Thirty-nine-year-old Const. Ron Williams was sentenced last month.

He was found guilty of failing to investigate a drunk driving complaint.

In 2011, a liquor inspector reported to police that an impaired driver was leaving the Whitney Pier Legion. Williams was at the police lock-up when he was assigned the call.

Williams was charged after he asked the jailer to warn the alleged drunk driver by phone that police were on their way to his house and to not answer the door. Williams also falsified a police report about the incident. He reported officers had searched for the man but hadn't found him.

An internal police investigation was launched after Williams was sentenced.

It would have determined penalties ranging from reprimand to dismissal.

The Cape Breton Regional Police say, now that Williams has resigned, the internal investigation has been cancelled.

Williams, an 11-year veteran of the force, was suspended with pay on Aug. 3, 2013.