In the decade-long, high-profile saga of the beleaguered Thunder Bay Police Service, no officer had faced more public scrutiny without conviction than former Staff Sgt. Michael Dimini.

That changed on February 20, when a court found him guilty of breach of trust and obstruction of justice, for what Justice Michael Block called “militantly illegal police conduct.”

Ontario Provincial Police tactical officers stood at the courtroom’s edges in response to an undisclosed security threat, as Block found Dimini guilty of the last series of charges in three trials the officer has faced in the last year. 

Block called Dimini’s actions a “brazen breach of the standard of responsibility and conduct demanded of a police sergeant by the nature of their office.”

TBPS leadership had repeatedly cleared Dimini in internal investigations. Multiple police services chased persistent rumours that the officer was dealing steroids and cocaine, finding nothing. It reached the point where the service issued public statements that it stood by Dimini, while it internally looked into officers for bullying him.

The latest charges were laid in connection with a November 2020 incident in which the former sergeant entered an apartment without a warrant in search of tools that had been stolen from the father of his then-common law partner. Dimini arrested the apartment’s occupants in what the court called “militantly illegal police conduct.”

Dimini was then found to have retroactively “concocted” a legal rationale. He went so far as to alter the incident report of a subordinate, without that officer’s knowledge or permission, to say police had been in fresh pursuit of a man with a warrant out for his arrest.

Block’s ruling leaned heavily on the testimony of Const. Kelly Walsh, a 33-year veteran of the local force, whom the judge deemed “impressive,” and could see, “no evidence he held any animus toward the defendant.”

None of this would have happened if Walsh and another colleague hadn’t gone over the heads of the Thunder Bay police to expose the criminality of their commanding officer.

The Frederica Street case

Walsh was among four constables who attended a call to a south side apartment complex on November 24, 2020. The father of Dimini’s common-law partner requested police assistance to retrieve his stolen television, which he found for sale on Facebook Marketplace. Some tools had also been taken from a shed in the robbery, but they were not listed for sale.

The seller’s Facebook profile bore the name and likeness of a man police knew to be associated with the illicit drug trade and who had an outstanding warrant. The four officers met in a parking lot nearby to devise a safety plan, in case he was there.

Dimini was the on-duty north side sergeant, but he made his way to the south side scene and remained out of view.

When the 34-year-old woman who came to the apartment’s front door to sell the TV saw police, she retreated back up the stairs. Officers followed her, although it was unclear whether Walsh said into the radio that she had the TV in “her hands” or “their hands.” That pronoun uncertainty lent support to Dimini’s belief that the person carrying the TV had been the same person who listed the TV for sale; the man who officers believed had an arrest warrant.

Now in her doorway, the woman handed over the TV to officers without incident, but she refused them entry without a warrant.

That’s when Dimini appeared in “a complete surprise to the officers on scene,” considering he was supervising officers on the other side of the city. He escalated the situation, commanding his officers, “Get out of my way. We’re coming in.”

The court found “chaos ensued,” with officers fighting other occupants, police “trashed” the apartment, and the woman testified Dimini knocked over pop and alcohol containers, calling her a “whore” and a “cunt” as he did so. Officers found the man with the warrant under some clothes and arrested him. Dimini found drugs and charged the woman with obstructing police, drug possession with intent to traffic, as well as possession of stolen property. No tools were recovered.

In his ruling, Block found Dimini not only entered the apartment unlawfully but he did so to, “exact extra-legal sanction on anyone the defendant believed to be potentially connected to the sale of [his family member’s] stolen property.”

Even though the man with the arrest warrant who posted the TV for sale on his own social media account turned out to be in the apartment, Walsh knew police would have needed a Feeney warrant to enter without permission. And the apartment’s occupant had been clear to officers that she was both denying them entry, and knowledgeable that police needed such a warrant.

Walsh asked Dimini how this was justified and alleged that Dimini told him, “It might have been a Charter breach, but it’s no big deal.”

Taking it upstairs

Dimini’s subordinate officers believed what they had done was illegal. When they reached out for help, they encountered resistance.

The Thunder Bay Police Service has a notorious record of incompetent investigation, systemic racism, and ineffective board oversight. In 2018, Ontario’s police watchdogs issued parallel reports that found overt and systemic racism in how Thunder Bay officers investigated the deaths of Indigenous people, as well as the board’s failure to see and correct those shortcomings in policy and governance.

In 2018 and then again in 2022, Ontario installed administrators to govern for the board. The second time, that action followed revelations that the Thunder Bay police had put a surveillance order on the phone of their Indigenous board chair. Ontario returned the board’s authority in April 2024, the same week Nishnawbe Aski Nation filed a complaint with Ontario’s new Inspector General of Policing, calling for the service to be disbanded. That office is expected to issue a Findings Report “early” this year.

Walsh appealed to the south side sergeant on duty that night, Todd Pritoula. Thunder Bay police had no formal policy regarding calls involving family members. But beyond the familial connection, Walsh told Pritoula and eventually the court that officers were, “unlawfully entering and technically assaulting people and we had no authority to be there.”

Meanwhile, Dimini was filing reports claiming officers were in fresh pursuit of the man with the warrant because he was the one seen carrying the stolen TV. Dimini claimed he was concerned that the tools he believed were in the apartment were actively being destroyed while officers stood outside.

Around 5 a.m. later that week, Dimini digitally altered Const. Kerry Dunning’s incident report, making it appear as though Dunning corroborated Dimini’s narrative that they had chased the man with the warrant in fresh pursuit. Dimini didn’t ask permission or notify Dunning that those changes had been made.

Walsh knew Dimini’s narrative to be false. He and Dunning took their case over Pritoula’s head to the watch commander, Staff Sgt. Joe Dampier. Walsh then attempted to persuade superintendent Dan Taddeo to take action, an officer who would later serve as interim police chief. He finally appealed to Staff Sgt. Gordon Snyder, who allegedly told Walsh, “We like to deal with these things informally.”

Even though Dunning was unaware how deeply Dimini had compromised him, he also sought an investigation, pleading his case about Dimini’s criminality to sergeants Justin Debuc, Ken Biloski, and Shawn Harrison. 

Whatever internal police investigation took place did not interview Walsh, Dunning, or either of the other two officers on the scene. None were questioned until the Ontario Provincial Police investigated Dimini in 2022.

And the Thunder Bay Police Service has since promoted every superior officer Walsh and Dunning urged to investigate Dimini’s actions that night, including Dimini, himself.

In his ruling, Justice Block chastised the Thunder Bay police’s internal operations.

“The failure of the Thunder Bay Police Service to interview any of the four original police attendees in the subsequent internal investigation of Sergeant Dimini in respect of this incident and the impressive speed in which the defendant was exonerated the following month suggest that the service was inclined to favour the interests of the defendant and that Walsh’s concern was unreasonable.”

Taking it outside

Having received no satisfaction internally, Walsh and Dunning took their concern beyond the police station to assistant Crown Attorney Trevor Jukes. Dunning told Jukes that police, “broke into this house and breached this girl’s Charter rights.” The Crown dropped the charges against the apartment’s occupants.

That’s when Walsh contends the abuse began internally, to deliberately trigger his post-traumatic stress and push him out of the workplace.

That winter, TBPS charged Walsh with discredible conduct under the Police Services Act after he attended a party of mostly police officers, violating COVID lockdown restrictions. Police leadership took the unusual step of charging Walsh $15,000 and a six-month demotion, then the service streamed his Police Service Act hearing online.

Walsh retained a lawyer after he says police chief Sylvie Hauth personally issued a letter to the Workforce Safety Insurance Board attempting to strip him of his post-traumatic stress treatment and disability benefits, stating “without provision of any evidence that Const. Walsh was lying about his disability and workplace injury.”

Walsh retired a year before schedule.

In July 2021, counsel for Walsh and Dunning filed complaints with the Human Rights Tribunal of Ontario. They claimed Dimini’s criminal conduct and the subsequent coverup exacerbated post-traumatic stress they’d experienced on the job, that their human rights were violated, and that they were experiencing reprisal.

Those HRTO complaints went to the Thunder Bay Police Service Board. The board and its legal counsel did not investigate their allegations, nor did they refer the officers’ concerns to either the OPP or the Ontario Civilian Police Commission for an independent investigation.

“Constable Walsh (retired) has experienced repeated triggered episodes due to the discrimination and harassment by the respondents,” the HRTO report reads. The failure to accommodate his PTSD upon the Sergeant Dimini incident and the continued discrimination and harassment by the Respondents resulted in Constable Walsh going on and staying on WSIB and then leaving the Service altogether, losing significant wages and pension entitlements in the process.”

Walsh filed three further complaints while Dunning filed four, both claiming they had faced the reprisal they’d feared for raising criminal concerns about Dimini. Walsh claims his unmet requests for action on Dimini reached as high as an expert panel the board had struck, and Malcolm Mercer, the Law Society of Ontario Tribunal head whom Ontario appointed administrator of the Thunder Bay Police Service Board when the province usurped its authority the second time.

Five years later, those HRTO complaints still have not been heard and their allegations remain untested.

Going public

Finally in 2022, Walsh and Dunning went to the media.

The pair became central subjects in the final episode of the Canadian Screen Award-winning documentary series, “Thunder Bay,” which aired on W5 and streams on Crave.

Before the documentary series was even released, the Thunder Bay police’s internal emails recommended that officers not watch it. Then-acting police chief Dan Taddeo, who officers insist refused to take action on their complaints about Dimini when he was a superintendent, told staff the program would be “sensational and unfair,” “disturbing, biased, and triggering.” Peer Support Team mental health lead Const. Jeff Elvish wrote, “this series is biased, and only includes the people who can forward a [sic] vile rhetoric.”

Ontario’s solicitor general requested the OCPC investigate in January 2023 and the OPP confirmed the attorney general had requested a “thorough and independent investigation” into allegations of criminal misconduct within TBPS in February, the same time the documentary was released. The OPP would arrest Dimini that December.

Walsh remains retired and Dunning remains a constable with TBPS. Neither attended court for Dimini’s conviction. When reached for this story, Walsh issued no comment.

Police board chair Karen Machado also declined to comment, but told media days before Dimini’s conviction that a large part of the $143,118 in 2025 indemnified legal costs were dedicated to Dimini’s cases.

Two high-profile cases with links to this case remain, including that of the former police chief and the service’s lawyer.

Former Thunder Bay Police chief Sylvie Hauth will face two charges of obstruction of justice, one charge of obstructing a public officer, and a charge of breach of trust by a public official. OPP charged former TBPS lawyer Holly Walbourne, who is now Dimini’s common law partner, with three charges of obstruction of justice, one charge of obstructing a public officer, and a charge of breach of trust by a public official.

Jon Thompson is an award-winning journalist and Local Journalism Initiative reporter based in Thunder Bay. He has reported on this story for TBNewswatch, TVO, CBC, APTN, Canadaland, and served as the senior associate producer on the Crave series, “Thunder Bay.” Contact him with tips and story ideas at Jon@ricochet.media.