The case relied largely on testimony from one of MacNeill's former cellmates

By Tara Fowler
Updated June 25, 2015 10:45 AM
Credit: Al Hartmann/AP

A Utah doctor who was found guilty of his wife’s murder is appealing his conviction.

Martin MacNeill was sentenced to life in prison for overmedicating his wife of nearly 30 years and then drowning her in a bathtub to start a new life with his mistress.

Lawyers are appealing his conviction on the grounds that key testimony in the case was tainted, the Associated Press reports.

The case relied largely on testimony from one of MacNeill’s former cellmates, who said that the doctor had confessed the crime to him.

However, the inmate in question had seen news coverage of MacNeill’s trial and was promised early release in exchange for his testimony, two facts that the jury who convicted MacNeill never heard.

“Whether the jury believed or disbelieved this informant was the linchpin in the prosecution’s case,” attorney Kent Morgan wrote in court papers obtained by the AP Wednesday.

MacNeill was also convicted of sexually abusing his daughter while she was visiting to help clean out her mom’s bedroom five weeks after her 2007 death.

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