The family of slain billionaire couple Barry and Honey Sherman is offering a reward of up to $10 million, the family’s lawyer announced, after criticizing the Toronto Police Service’s investigation as falling “below the standard.”

The bodies of the Shermans were discovered in the basement of their home on Old Colony Road in an affluent area of North York, on Dec. 15, 2017. Police said the couple was found hanging from a railing of an indoor swimming pool. The two had belts tied around their necks.

Shortly after the discovery, police announced there were no signs of forced entry into the house and police were not looking for suspects.

Brian Greenspan, the family lawyer, slammed that initial assessment as a “misguided and unfounded conclusion that left the wrong impression that this was a self-inflicted crime.”

“That comment set the wheels in motion and conveyed a false sense of security to the public and devastation for the family.”

Media reports initially cited police sources as saying the prevalent theory in the case was that it was a murder-suicide.

The Sherman family hired a private investigative team, which included several retired police detectives and even former Chief Forensic Pathologist Dr. David Chiasson, who conducted a second autopsy.

On Jan. 26, more than a month after the discovery, police publicly classified the case as a targeted double homicide.

Greenspan says it was Chaisson’s autopsy findings that let police to make the “belated” conclusion.

The cause of death has been determined to be ligature neck compression. Authorities have released few other details about the investigation.

Greenspan pinpointed the areas of the police investigation that the private investigative team thinks were sub-standard, including the examination of the points of entry and what he called a “failure to understand that the bodies were staged post-mortem in a very deliberate manner.”

“The police also missed at least 25 palm or finger print impressions that were discovered by our private team,” Greenspan said.

He then announced the $10 million reward for “information leading to the apprehension and prosecution of those responsible.”

“We have seen failings and deficiencies. The failings and deficiencies are what have prompted the Sherman family to take this action,” Greenspan noted.

Toronto Police Chief Mark Saunders addressed Greenspan’s comments later Friday afternoon, saying the investigation was and continues to be conducted at a “very high level of professionalism.”

“I also want to clarify that the Toronto Police Service never reached a premature conclusion with this investigation,” Saunders said. “The investigation was not taken lightly and is still not taken lightly.”

Saunders said that up to 50 officers were involved in the case and over 2,000 hours of video footage was recovered. The Sherman’s home was searched thoroughly over six weeks, he added.

The service’s homicide unit and a forensic pathologist was on scene to help officers navigate the crime scene, Saunders said.

In response to specific criticism of the service’s investigation, Saunders suggested that the private investigation team assembled by the Sherman family does not have all the information.

“There are very few people who have the entire investigation – Mr. Greenspan does not have the entire investigation.”

Saunders also said that said while rewards don’t necessarily help police investigations, “anything that helps lead to a successful conclusion is, I think, a good thing."

Greenspan offered, several times during the news conference, to work with police in sharing the findings and resources available to the private team. He also said that the team does trust that the police share their objective of finding the person or people involved.

The reward is expected to work on a "sliding scale" and a panel has been set up to assess the value of the information. Greenspan also invited a member of Toronto police to sit on the panel.

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