Ontario's auditor general says a backlog of criminal cases in the court system is growing, and courtrooms only operate for an average of 2.8 hours a day.

Bonnie Lysyk's annual report looked at various aspects of the justice system, including criminal and family courts, jails and detention centres, as well as coroners' operations.

She found that most of the highest-billing coroners, who are also physicians, performed death investigations on their own patients last year.

The report also says that Office of the Chief Coroner doesn't have procedures for inventories of bodies, leading to some being found in the wrong cooler.

In the courts, Lysyk found that the number of criminal cases awaiting resolution grew by 27 per cent to about 114,000 cases, while the average number of days needed to deal with a case grew by nine per cent.

The Supreme Court of Canada ruled in 2016 that cases must be dealt with in certain time frames or be tossed, and Lysyk says 191 cases in Ontario have been stayed in the last three years because of that.