JEFFERSON CITY, Mo. (AP) - A man sentenced to death for murdering a 6-year-old girl he abducted from her father’s St. Louis County home is seeking a new trial, arguing his lawyers should have pursued a defense that he suffered from brain damage.

The Missouri Supreme Court heard arguments Wednesday on whether to grant a new trial or sentencing hearing for Johnny Johnson in the July 2002 slaying of Casey Williamson.

Johnson admitted at his trial that he killed the girl. But his attorneys argued he did not qualify for the death penalty because mental illnesses made him incapable of acting with “cool reflection.”

Johnson’s current attorney argued Wednesday that the defense should have also hired a neuropsychologist to testify about Johnson’s brain damage.

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