CHICAGO (CBS) — Thomas Peterson — son of accused wife-murderer Drew Peterson and of Kathleen Savio, the woman Peterson is accused of killing — is taking a legal stand in defense of his father.

In an impassioned letter sent to Sun-Times columnist Michael Sneed, Thomas Peterson, 18, said he is no longer a minor and has signed a document releasing his father from all financial claims arising from the death of his mother. His aunt and grandfather have filed a wrongful death suit on Thomas Peterson’s behalf.

“Because I know my father is innocent, I am releasing him from the lawsuit brought by Henry J. Savio and Anna Doman on my behalf while I was a minor,” the son wrote in the letter.

“Nobody is pulling the wool over my eyes. I know to an absolute 1000% moral certainty that my father Drew Peterson is innocent in the death of my mother Kathleen Savio,” he wrote. “Do not forget I was with my father the entire weekend that my mother died.”

Joel Brodsky, Peterson’s attorney, said he plans to send the document excising Thomas Peterson’s name from the Savio suit to attorneys for the Savio family by Monday. The wrongful death suit was also filed on behalf of Thomas’ brother and Savio’s youngest son, Kristopher, 16.

Kathleen Savio’s 2004 bathtub death was originally classified as an accidental drowning. But after a 2007 exhumation it was reclassified as a homicide and Drew Peterson, a former Bolingbrook police sergeant, was charged with the murder. Now jailed, he also is considered a suspect in the 2007 disappearance of his fourth wife, Stacy Peterson.

Brodsky told CBS 2’s Mike Puccinelli Drew Peterson is aware of his son’s stance.

“He’s proud of his son for not being anybody’s fool and being his own man and standing up and saying what he thinks is right,” the attorney said.

Savio’s family members did not return phone calls seeking comment. Stacy Peterson’s sister, Cassandra Cales, released a statement about Thomas Peterson.

“Thomas Peterson is a very intelligent young man,” she said. “But until he personally sees the evidence, how can he make an educated decision?  Maybe now that he is 18, he can sit down with the state, review the evidence and then make a decision.” 

Contributing: Sun-Times Media Wire

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