Steven Clark, a convicted killer who is appealing the verdict against him, has support from an unlikely source.

Felicity Ferrell, the mother of murder victim Robert Wagner, recently sent letters to the Maine Supreme Judicial Court, seeking a new trial for the man who killed her son. Ferrell says the 2007 murder trial was tainted.

“At no time have I said Mr. Clark did not shoot my son. What I have contested from day one are the circumstances leading to the charge of intentional murder,” Ferrell wrote in a letter to the court dated May 1.

“My son was among buddies when he died. The buddy system failed.”

Clark’s defense lawyer, Joel Vincent, will argue the appeal Thursday morning in front of the law court in Portland. Vincent says the state did not prove its case and the jury was influenced by improper actions by the prosecuting attorney.

Clark is serving a 43-year sentence for the Feb. 15, 2006 killing.