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UCF #104200218

New Information Closes Decades-Old Muriel Mann Cold Case

Muriel Mann

Muriel Mann


Because 38 years have passed and those involved have since died, police said they "will never be given the opportunity to validate our findings in court."

Saint John, New Brunswick — After 38 years, the gruesome murder of Rothesay nurse Muriel Mann has been solved with new information, clearing the name of Mann's former boyfriend 17 years after his own death, according to the Kennebecasis Regional Police Force.

On March 6, 1984, Mann's body was discovered in the freezer of her Hillhurst Drive home by two friends after they checked in her. At the time of the murder, Mann had been dating John Mavon, and according to his daughter Diane Heans, Mavon, who hadn't heard from Mann in a couple of days, was there at the home with a next-door neighbour when Mann's body was discovered.

Despite public appeals, the Mann murder case grew cold over time. But on March 17, 2022 - a little over 38 years to the day of the murder - Heans says she received a call from the Kennebecasis Regional Police Force and was told her father, who had died in 2005, was no longer considered a suspect in Mann's 1984 murder.

Family and friends have known Mavon was innocent for decades, Heans says, but now, hopefully other people will believe it too. While police never formally accused Mavon of being a suspect, Heans says a "cloud" has followed her family's name for nearly 40 years.

When approached by the Telegraph-Journal with this information, the Kennebecasis Regional Police Force confirmed in a press release Wednesday, March 30, 2022 that Mavon is not a suspect in the homicide and the Mann case has been closed.

"As a result of new information received anonymously from the public, the KRPF Criminal Investigation Division recently re-opened this cold case, and now have new and updated information,” police said in a news release.

Detectives identified new suspects and, in response to a media inquiry, confirmed that John Mavon is not one of them.

Police said they are "confident" that Mann had become aware of criminal activity by someone she knew and was murdered due to fear she might report it to police.

"Her children were never considered suspects and have been updated on these new findings," said police.

Because 38 years have passed and those involved have since died, police said they "will never be given the opportunity to validate our findings in court."

Memorials Memorials  New!

Citing respect for everyone concerned, police said they will not provide more information on the case.

"Our investigation is now complete, and the file is closed."

Sandra Mlodzik

Sandra Mlodzik

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4 + 6 = ?

Random violent crime seems less common. There are definitely people caught in the wrong place at the wrong time that end up victims, but generally the serious assaults/stabbings are between people known to each other.

Enedina S.

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