Auditor General John Doyle says the Police Act is being followed.
"The complaints and investigations we audited were found to be well-documented and comprehensive — providing sufficient evidence that complaints are respectfully addressed and that all investigations are conducted in a thorough manner," reads the report.
"We observed that none of the complaints we reviewed were treated as trivial."
Doyle added there is growing appreciation of the need for civilian oversight.
"The Auditor General has concluded that, overall, police complaints are being managed in compliance with the [Police] Act," said a written release.
"The commissioner promotes thorough and competent investigations of police complaints by exercising discretion as provided by the Act, and the OPCC has taken steps that are consistent with the Act to increase public awareness of the police complaint process."
The audit, ordered by the legislature in May, looked into the use of stun guns and how police complaints are handled.