A man who said he was heeding a call from God when he gunned down his parents and used a chain saw to cut up his mother's body pleaded guilty Monday to first-degree murder.

Philip Badowski, 23, entered the plea after a judge turned down his attorney's motion to suppress evidence in the December 2004 slayings. He was sentenced to life in prison without parole.

Badowski's attorney had argued unsuccessfully that the police search of the home in suburban Hixson was inadmissible, because officers had to break into the parents' bedroom to find the bodies.

A state psychiatric evaluation (search) previously showed Badowski competent for trial, but public defender Mary Ann Green (search) said after Monday's hearing that Badowski "is mentally ill."

Green said he is afflicted with "schizophrenia (search) or a bipolar disorder (search) or both."

An investigator previously testified that Badowski told officers who interviewed him that he killed his parents, Chester "Chet" Badowski Jr., 47, and Christine Badowski, 46, because "God told me to."

Badowski also previously said the killings were "spur of the moment" after his parents scolded him when they returned from a weeklong mission trip to Haiti (search), where they worked drilling wells.

"They were cussing and calling me bad names because I had some friends over while they were out of town," he said in the interview.