ATASCADERO, Calif. -

The Atascadero man who police say admitted to killing his neighbor last year, pleaded not guilty by reason of insanity.

Mark Andrews appeared in a San Luis Obispo courtroom Tuesday morning for the May 2013 murder. The victim was Colleen Barga-Milbury, a former Atascadero State Hospital employee.

Andrews has a history of mental health issues, including being ordered to attend mental health counseling after a prior arrest.

Andrews is scheduled to be back in court on March 4.