CASPER, Wyo. (AP) — A judge has postponed the trial of a Wyoming man accused of breaking into his parents’ home and fatally shooting his mother when she confronted him in the living room.

The Casper Star-Tribune reports a technical problem is preventing the Wyoming State Hospital from providing 27-year-old Andrew Steplock’s mental health evaluation until the end of the month. The trial will now likely be held in December.

Steplock, who was set to go to trial Aug. 26, has pleaded not guilty and not guilty by reason of mental illness to four charges, including murder.

Police responded to an alarm south of downtown Casper on Feb. 26 and found 58-year-old Deborah Steplock with a gunshot wound to the head. Detectives say the son told them he broke into the home to steal from his parents.