One of Ontario's police watchdogs says unnecessary and illegal strip searches have become commonplace.

In a special report today, the Office of the Independent Police Review Director says strip-search procedures across the province are inconsistent.

It also finds justification to do them is frequently lacking and data collection is inadequate.

The report, which makes 50 recommendations, says police conduct more than 22,000 strip searches a year.

The report urges police to take a hard look at their practices.

It calls the searches intrusive and often a violation of privacy rights.

"It is extremely concerning ... police continue to conduct strip searches in violation of the law," review Director Gerry McNeilly says in a statement.

"This comes at a high cost to those directly affected by humiliating and intrusive searches and to the justice system, especially where unlawful searches result in the exclusion of evidence or the staying of charges."