By Cleve Bryan

By Cleve Bryan

CAMDEN, N.J., (CBS) — The children of former Cooper Health System CEO John Sheridan say the investigation into their parents’ deaths last September was sloppy and misdirected from the start.

Mark Sheridan, one of John and Joyce’s sons who is a lawyer, sent a scathing letter Monday to the Somerset County Prosecutor’s Office.

He claims they botched his parent’s investigation saying, “Your office set out to prove the premature conclusion of its investigators.”

Tuesday Mark Sheridan went further to say, “They never conducted or performed even the basics of an investigation. All they did was try to prove that this was a murder-suicide.”

On March 27th the Prosecutor’s Office released a 7-page report detailing stab wounds to both Sheridans and concluded, ”John Sheridan killed Joyce Sheridan and, thereafter, committed suicide.”

The Sheridan’s had their own autopsy done by renowned forensic expert Dr. Michael Baden.

He says John Sheridan’s wounds were not self-inflicted, as the Prosecutor’s Office claimed, and left open the possibility both Sheridans were murdered.

Mark Sheridan says possible murder weapons were neglected or not sought by investigators who he got into a shouting match with in his parent’s front yard last Fall.

The Prosecutor’s Office’s only comment Tuesday is they stand by their investigation.

The Sheridan’s are suing to have their father’s death certificate changed so it doesn’t say he killed himself.

They are also putting together a $250,000 reward for information that leads to the conviction of his parents’ real killer(s).

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