The father of the Toronto police officer charged with severely beating a teenager in Whitby, Ont., last year repeatedly contacted Durham Regional Police as they investigated the assault and provided them with false information in an attempt to cover up the crime his son is accused of committing, a new complaint alleges.

Lawyers for Dafonte Miller, who was 19 at the time he was beaten, have filed a complaint with the Ontario Independent Police Review Director (OIPRD), a civilian oversight agency, alleging that police in Toronto and Durham Region "conspired to deliberately conceal" the crimes Toronto police Const. Michael Theriault and his brother, Christian Theriault, a civilian, are charged with committing.

The father of the two men, John Theriault, is a veteran Toronto police detective, according to the complaint.

None of the allegations in the complaint have been proven in court.

The brothers were charged by Ontario's Special Investigations Unit (SIU) with aggravated assault, assault with a weapon and public mischief in the December beating of Miller, who permanently lost sight in one eye. They are currently out on bail awaiting trial.

What followed was an "orchestrated coverup motivated by corrupt purposes and enabled by weak police oversight legislation," according to Miller's lawyer, Julian Falconer.

Theriault brothers

Michael and Christian Theriault arrive for a court appearance on Wednesday, Aug. 2. The brothers have been charged with assault and are out on bail awaiting trial. (Lisa Xing/CBC)

Falconer announced the OIPRD complaint at a news conference at Queen's Park on Wednesday where a coalition, including the Ontario Human Rights Commission, called on the government to improve police oversight and make legislative changes to clarify when police are to notify the SIU.

Referring to the Miller case, Falconer said it is a "poster child for all that is wrong with civilian oversight of police."

Alleged interference from father

Toronto police Chief Mark Saunders confirmed in a July 27 statement that his force's professional standards unit was informed of the allegations involving Theriault and decided not to notify the SIU.

According to the complaint, John Theriault is assigned to the professional standards unit.

The complaint alleges that he "repeatedly contacted DRPS investigators to gain information relating to the status of the investigation and to provide additional false information about injuries suffered by his son Christian to aid in the concealment of the crimes committed by his sons."

Saunders has asked Waterloo Regional Police to investigate the handling of the Miller investigation and a Toronto police spokesperson declined to comment on the OIPRD complaint while that investigation is ongoing.

'Failure to properly investigate'

The complaint blasts the investigation Durham Regional Police conducted after Miller's beating — an investigation that initially led to Miller facing charges of theft under $5,000, two counts of assault with a weapon, possession of a weapon (a pole) and possession of marijuana.

It's alleged Durham police failed to interview two eyewitnesses who presented themselves to officers and said they were able to view most of what took place from their windows.

Julian Falconer Dafonte Miller Durham police beating

Toronto lawyer Julian Falconer is representing Miller, who lost an eye as a result of the beating. (Martin Trainor/CBC)

The complaint alleges Durham police "blindly" accepted the account of Michael and Christian Theriault that they were assaulted by Miller with a metal pipe, despite not having sustained any injuries or, the complaint says, "a single scratch."

It's also alleged that Durham police never asked Miller how he sustained his severe injuries.

It was the teen's lawyer, not police, who contacted the SIU about Miller's injuries in April. Charges against him were dropped in May, and the Theriault brothers were charged in July.

The SIU conducts criminal investigations into circumstances involving police and civilians that have resulted in serious injury or death.

Failed to investigate

The Theriaults allegedly told investigators that Miller had broken into a vehicle, but officers failed to investigate whether there had actually been a break-in.

A spokesperson for Durham Regional Police Services said they could not comment on the allegations in the complaint, citing the ongoing investigation by Waterloo Regional Police and the ongoing criminal prosecution of the Theriault brothers.

New details about incident

Miller's complaint contains the most detailed account yet of what allegedly occurred on Dec. 28, 2016.

The account has not been tested in court.

According to the document, Miller was walking with friends near Michael Theriault's home in Whitby around 2:30 a.m.

The Theriault brothers were drinking beer and smoking cigarettes in the garage, the complaint says, when they asked Miller and his friends if they lived in the area. Miller replied that they lived down the road and asked Theriault why he  wanted to know.

Theriault responded that he was an off-duty police officer and could ask whatever he pleased, the complaint says.

After Miller and his friends began to walk away, it's alleged the Theriault brothers exited the garage with one of them carrying a metal pipe.

Miller was concerned for his safety and ran, the complaint says, but the brothers caught up to him and said they had witnessed youths in their vehicle about two hours earlier. Miller said it wasn't him.

In the complaint, it is alleged that Miller was thrown to the ground and beaten by both brothers and struck multiple times in the face with a pipe by Michael Theriault.

At one point, Miller managed to get away from the men and banged on the door of a home to ask for help, the complaint says.

Eventually, it's alleged Christian Theriault called 911 to report that his brother, an off-duty police officer, had a suspect in custody who he said was breaking into their vehicle.

As a result of the alleged beating, Miller's left eye was dislodged from its socket and split in four pieces. The complaint also says he suffered reduced vision in his right eye, a broken orbital bone, a broken nose, and bruised ribs.

Miller remained in handcuffs during the trip to Lakeridge Hospital in Oshawa, the complaint says.

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