As Det. Const. Alec Tompras of York Regional Police pressed a robbery suspect for information on Aug. 2, 2012, a camera captured the interview from above.

"I know for a fact that you were there that day," Tompras told Gil Kim, who was being interrogated about an armed robbery of a Rogers store in Markham, Ont., north of Toronto.

The footage of the interrogation became crucial as Kim's lawyer sought to have the charges thrown out.

In her 2017 decision, Superior Court Justice Cory Gilmore questioned why Kim was seated facing away from the camera during the interrogation. Recordings show Kim's co-accused were interviewed facing the camera.

An Ontario judge said York Regional Police recorded this interview from behind to conceal injuries police inflicted on a robbery suspect in 2012. (Court exhibit)

Gilmore threw out the case against Kim, who admitted to participating in the crime, after finding that police had assaulted him and covered up their actions.

"The only inference to be drawn" from Kim's position to the camera, Gilmore wrote, was that it was chosen "to ensure that the blood on Mr. Kim's shirt or any facial swelling would not be seen on camera."

Gilmore called Tompras's testimony about where Kim sat "disingenuous" and "bordering on ludicrous." The judge also found Tompras "fabricated" a claim about having notes to explain "how he was able to come up with precise times for events hours after they occurred."

Investigation finds dozens of other cases

Kim's case is just one example of a problem that's more prevalent than many Canadians might realize. CBC News reviewed more than 50 criminal cases over the past five years where judges found that police officers had given false or misleading testimony, and the case against the accused fell apart.

The results of the investigation are no surprise to James Lowry, a former Toronto police officer who investigated misconduct in his own police service before becoming a defence lawyer.

Lowry worries some officers may have an "end justifies the means" mentality.

"We have to do this in order to clean up the streets to help the public," he said, describing the rationale of some officers.

"That attitude has to change."

Police officer-turned lawyer James Lowry says 'a small element' of police officers will break the rules if it leads to arrests. (Travis Golby/CBC)

York Regional Police dispute Gilmore's findings. In an email to CBC News, the police force said an investigation by the neighbouring Peel Regional Police "clearly refuted the conclusions drawn" by the judge.

York Regional Police maintain officers "did not provide false information."

"It would appear most likely that Mr. Kim fabricated the assault allegation."

'I make these kinds of findings very reluctantly'

CBC News learned of dozens of cases through news reports, filing access to information requests, speaking to defence lawyers about their recollections of cases, listening to recordings of courtroom proceedings, and other methods. The search found cases involving police in Toronto, Winnipeg, Vancouver and other cities.

Lawyer Tom Engel maintains a digital library of information on police misconduct that includes files on officers in Edmonton, Calgary and the RCMP.

He said the records allow him to provide information on police officers to other lawyers and to help fill in gaps that develop when old police discipline records are expunged.

Engel, who maintains the records as chair of the policing committee for Alberta's Criminal Trial Lawyers' Association, believes information on police misconduct, including problematic testimony, should be available via a simple database search.

"Any citizen should be able to go in, look up the name of a police officer, and find out what his or her conduct record is," he said.

Edmonton criminal defence lawyer Tom Engel said if the police union's views on Partington's suspension reflect the views of EPS members, that shows there is a "real cultural problem" within the service. (Manuel Carrillos Avalos/CBC)

But any database of information on police who have given false evidence in court would require clear findings from judges. And defence lawyers who spoke with CBC News said judges are sometimes reluctant to put that on the record.

In 2015, a Toronto police officer testified that he noticed pills containing codeine on the passenger seat of a vehicle during a traffic stop.

The pills were in a bottle with the label ripped off, the officer said, which suggested the driver had no legitimate reason for having the pills. The officer also claimed to be able to see the lettering on the pills.

The officer said he did not believe the man when he claimed the pills were his wife's, and arrested the driver for drug possession. A subsequent search turned up crack cocaine, according to a courtroom recording reviewed by CBC News.

Superior Court Justice Nancy Spies tossed out the evidence and rejected the officer's claims. In court, she suggested giving her reasons orally to prevent a written version from being posted to CanLii, a public online database where judges' decisions are sometimes posted.

"I tend to, very often, give written reasons, but I can tell you, I make these kinds of findings vis-a-vis a police officer very reluctantly," she said in a courtroom recording.

Defence lawyer Monte MacGregor told CBC News he protested, and Spies changed her mind. In her reasons, which are available on CanLii, Spies says the officer's observation about the pills would require "something akin to X-ray vision."

Toronto officers called out in court

Some officers have been accused of giving false testimony in multiple cases. When that happens, it is difficult to tell how — or if — their police service responded to a judge's findings.

Among the officers criticized for providing misleading testimony is Toronto's Const. Richard White, who was recently accused of stealing money during a 2017 drug and gun bust.

Toronto police announced last month that White and Const. Aseem Malhi face charges of theft, perjury and obstruction of justice.

"It is alleged that officers provided false or misleading testimony" at a preliminary inquiry, the service said in a press release.

Wojciech Gorski, another officer involved in the 2017 bust, was criticized by a judge in 2016 for providing misleading testimony in a different drug case, according to records reviewed by CBC News.

Even if a court rejects an officer's testimony, or makes a finding which is inconsistent with the officer's testimony, it is not necessarily a finding that the officer's evidence was dishonest. - Connie Osbourne, Toronto Police Service spokesperson

CBC News has learned that in 2016, a judge sharply criticized White's testimony in a separate drug investigation, saying it was replete with "serious credibility and reliability issues."

In that case, as well as several others reviewed by CBC News, it's difficult to determine what consequences, if any, the officer faced for giving false testimony, and how closely police services have been tracking judicial findings.

A record from the Public Prosecution Service of Canada (PPSC), obtained by CBC News through an access to information request, shows the Crown attorney from White's 2016 case emailed colleagues after the judge's ruling.

The prosecutor described the judge's decision and asked colleagues if the service should report the finding to the police.

The Toronto Police Service said it had closed an investigation into the matter.

In an email to the CBC, Toronto police said provincial legislation prevents the service from discussing the outcome of any investigation into an officer's testimony, unless it resulted in an appearance before a disciplinary tribunal.

"Even if a court rejects an officer's testimony, or makes a finding which is inconsistent with the officer's testimony, it is not necessarily a finding that the officer's evidence was dishonest," spokesperson Connie Osborne wrote.

A review of more than five years' worth of Toronto police tribunal records revealed few references to officers giving false or incorrect testimony. Toronto police pointed to one case in which an officer was found not guilty of professional misconduct after a judge said he falsely claimed he had witnessed a drug deal.

It's difficult to determine how often the PPSC, which prosecutes drug offences and other crimes, refers cases of alleged police dishonesty back to police services for investigation.

Some PPSC records released in response to the CBC's access to information requests were heavily redacted.

PPSC declined to answer questions about referring cases to police.

"Any discussions between the PPSC and the police regarding an officer's conduct or testimony is confidential and cannot be provided," a PPSC representative said in an email.

'Corrosive' problem

CBC News sent excerpts from judges' findings to about a dozen police services, and asked whether they were aware of the rulings, if they had investigated their officers, and other questions.

Some declined to comment, while others, like the Toronto and Peel police services, provided brief comments on all or most cases shared by CBC News, including which ones had been investigated.

Some services chalked up an officer's misleading testimony to inexperience.

The Toronto Police Service said it was previously unaware of several criminal cases CBC News inquired about, which are accessible online.

To lawyer Tom Engel, the CBC's findings illustrate a "corrosive" problem that fosters disrespect for the law and threatens innocent people.

"You're looking at the tip of the iceberg."