When a person is caught out in a lie, their word becomes suspect in future. Could any concept be simpler? A 5-year-old can grasp the logic. Why is it, then, that police officers with a documented history of lying under oath are permitted to testify in our criminal courts without being compelled to confront their previous pattern of deception? The answer lies in an unfortunate combination of legislative inaction, judicial restraint and the legendary “blue wall” of police solidarity.

‎We have seen an ever-expanding stream of press exposés in recent years about lying police witnesses. This week alone, we learned that Ontario Superior Court Justice Cory Gilmore used words such as “incongruous” and “bordering on ludicrous” to describe police testimony she found to have been concocted.

Given the significant trust that our courts place in the honesty of police witnesses, officers who lie‎ erode public faith in the courts and risk the conviction of innocent defendants. Surely, the time has arrived for the justice system to correct this disturbing problem.

‎It is only in the past generation that judges have truly come to grips with the fact that some officers embellish facts, paper over investigative flaws or simply outright lie in order to help secure a conviction.

This sort of finding is not made lightly. A judge concludes that an officer lied only after becoming convinced that the testimony was fabricated. Judges are keenly aware of the serious impact such a finding may have on a legal proceeding. They explain these findings in minute detail, backed up with evidentiary discrepancies that expose the false testimony.

Any finding of this nature ought to sound an alarm that is heard throughout the justice system. ‎Indeed, Ontario’s former attorney general John Gerretsen made it a requirement in 2012 that trial prosecutors report to their supervisors all instances where judges have drawn adverse conclusions regarding a police officer’s credibility in court for further investigation.

Sadly, this commendable step forward has largely gone to waste. Occasions where this protocol is followed have gone unreported and unmonitored. Furthermore, these instances of misconduct are inadmissible in court. This is because a body of decisions from this province’s highest court holds that a judge’s findings of fabricated testimony ‎in one case cannot be used to challenge an officer’s credibility in a subsequent case unless that officer was charged and convicted of a crime, such as perjury or obstructing justice, or found guilty of a disciplinary offence.

This represents an obvious flaw in Ontario’s police oversight legislation, a flaw that is aggravated by the reality that police forces often investigate their own officers when it comes to perjury or discipline. Not surprisingly, charges are rarely laid. Insofar as we are able to tell in the absence of reliable statistics, most officers who are caught lying can continue to fabricate evidence in one case after another without their pattern of deception ever being exposed in court.

Two clear responses are available in order to resolve this intolerable anomaly. First, Ontario’s Attorney General Yasir Naqvi could expand the mandate of the Special Investigations Unit (SIU) to investigate any judicial finding that an officer has lied in court, as suggested by Justice Michael Tulloch several months ago in his report on policing reforms. The result would almost certainly be more prosecutions as well as greater transparency. As an additional safeguard, the SIU should be required to publicly report and explain not only cases where charges are warranted but those that it deems unworthy of prosecution.

‎At the same time, appellate courts should reconsider the common law rule that prevents trial judges from considering previous court proceedings where a judge found an officer to have falsified evidence as a witness.

The principles of fair play lose their meaning when liars are not caught out and dealt with. As any 5-year-old can attest.

Daniel Brown is a criminal defence lawyer and a Toronto director with the Criminal Lawyers’ Association.