It is said there are six degrees of separation among all of us, but the link between Drew Peterson and Greg Long is downright uncanny.

Long and Peterson are both behind bars fighting murder charges. And the lives of both suspects could come down to what one man, forensic pathologist Dr. Bryan R. Mitchell, had to say. Long believes the connection is so significant that he pleaded for help after realizing the coincidence.

Mitchell is the Will County coroner who performed the original autopsy on Peterson's third wife, Kathleen Savio.

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On March 1, 2004, Savio was found dead at her home in a waterless bathtub, soaked in blood. After examining her body, Mitchell theorized that Savio's death could be "ascribed to drowning."

Based partly on Mitchell's autopsy of Savio, a coroner's jury determined her death to be an accidental drowning.

After the disappearance of Peterson's fourth wife in October of 2007, Will County authorities approved the exhumation of Savio's body for a second autopsy.

That examination led to a far different conclusion, and the case was reclassified a homicide. On May 7, 2009, Peterson was indicted by a Will County Grand Jury and charged with Savio's murder.

Long has been locked up for almost nine years at the Hill Correctional Center, a medium security state prison in Galesburg, Ill. He was found guilty of murdering one of his best friends on October 25, 2000.

But all this time, he stood behind the belief that his trial had been flawed by a major error in the autopsy. That autopsy also was performed by Mitchell.

Jobless and homeless, Long says he was living in an abandoned truck in Joliet with his friend David Henker in the fall of 2000. They spent their days drinking heavily and using drugs, he says.

Long claims he found Henker dead after a night of wild partying together, and stood by his story that his friend died of an overdose in an interview with FOX Chicago affiliate WFLD.

Henker's autopsy did indeed detect cocaine in his system as well as a blood alcohol level of .446, more than five times the legal limit. But Henker's body was badly burned, because their truck cab had caught fire. The deep bruises on Henker's neck led Mitchell to conclude Henker was strangled. But no DNA from Henker was detected in fingernail scrapings collected from Long the day after his friend's death.

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