The Pennsylvania Supreme Court has ordered another hearing to determine whether mass murderer George Banks is too mentally ill to be executed.

A state court ruled in February 2006 that Banks, who killed 13 people in a 1982 shooting rampage, was delusional, psychotic, and had no capacity to assist in his own defense.

But the high court, in a ruling filed Friday, said a Common Pleas court erred in barring the commonwealth's psychiatrist from testifying and then denied a second state expert witness time to prepare properly.

The justices ordered the lower court to "expeditiously" conduct a new hearing to allow the state to "present a meaningful case" on Banks' competency. They warned the lower court "not to be diverted by tangential notions and assertions."

Chief Justice Ralph Cappy, joined by Justice Cynthia Baldwin, dissented, saying the evidence of Banks' incompetency "is nothing short of overwhelming and a second competency hearing is unwarranted."

The state Supreme Court halted Banks' execution in December 2004 and ordered the competency hearing. The U.S. Supreme Court held in 1986 that it is unconstitutional to execute the insane.

Banks, a prison guard, picked up his AR-15 semiautomatic rifle shortly before 2 a.m. on Sept. 25, 1982, and began shooting. He killed seven children, five of them his own; his three live-in girlfriends; an ex-girlfriend; her mother; and a bystander in the street.

Banks, who is biracial, maintained that he shot his children to spare them the racial prejudice he endured in Wilkes-Barre. Prosecutors noted his history of abusing women and said he had been involved in a nasty custody battle with one of the victims.

His lawyers have said mental illness played a role, though the trial jury rejected an insanity defense.