Andre Marin publicly identified a police officer who he believed was behind a Twitter account using the fake name "Joe Mayo" that was directing offensive messages at him.
The tweets appeared on Aug. 8, before Marin was to give a news conference on the death of 18-year-old Sammy Yatim in police shooting on a Toronto streetcar.
Marin took to Twitter minutes before the news conference started to identify Det.-Const. Scott Dennis as the source of the tweets calling Marin a "card carrying member of Al Qaida" and telling him not to stick his nose "in business it doesn't belong."
The ombudsman also tweeted Dennis' badge number and his salary, as well as reposting messages people sent him, complimenting him for outing the officer on Twitter.
But the Durham police force said Monday that Dennis was on annual leave at the time and did not know about the account, which investigators said was set up by a fellow officer without his knowledge or consent.
As of Tuesday evening, Marin said he didn't see the need at the time for an apology to the wrongly accused officer, but after police officials met Wednesday with members of the ombudsman's staff and gave them "concrete information" exonerating Dennis, Marin said he was sorry.
"Their investigation is still ongoing," Marin wrote in a statement. "However, they provided their assurance that they are confident, based on the digital, witness and other evidence they have gathered, that Det.-Const. Scott Dennis — whose name and badge number were used to create the Twitter account in question — was in no way responsible for it."
Marin said he reached out to Dennis and also spoke to the officer's lawyer.
"In light of this information, I apologize to Det.-Const. Dennis for any distress that my role in this matter may have caused him and his family," the ombudsman said in his statement.
"I understand this has been a very difficult time for Det.-Const. Dennis, and I hope that in addition to my apology, he will also receive a proper apology from both the colleague who fraudulently impersonated him, and his police service."
Durham police haven't named the officer who they believe is responsible, but say the detective, who is facing disciplinary charges, remains on duty but has been removed from his current assignment.
The organization representing front-line police officers in Ontario criticized Marin earlier Wednesday both for publicly naming Dennis as well as what the organization called his failure to take responsibility for his mistake.
"Mr. Marin's approach was slipshod and his attitude is cavalier," said Dave McFadden, president of the Police Association of Ontario.
"His behaviour is unacceptable, particularly coming from someone holding such a high position of public trust and authority. Mr. Marin, of all people, knows there is a process in filing complaints for investigation. If he had a concern, he should have followed that process. Instead, he publicly maligned an innocent person."
A message seeking comment from Dennis' lawyer was not immediately returned.
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