PITTSBURGH — A 13-year-old girl accused of fatally shooting her father was sexually abused by him and the years of abuse led her to kill him, her attorney said Tuesday.

Matthew Booth, 34, died of a shotgun wound to the head early Monday. The girl told investigators she used a 12-gauge shotgun to shoot him in the face at about 2:20 a.m.

Police have not discussed a motive for the killing, but the girl's attorney, Patrick Nightingale, said she told investigators "that there was a six-year history of molestation and repeated rapes."

Police had collected evidence and were conducting a rape kit on the girl, said Nightingale, who said he would try to have the case moved to juvenile court. He said he had met with his client, and "under the circumstances, she's doing about as best as one could hope."

Prosecutors had agreed to move the girl from prison to a juvenile detention facility, and that is expected after a bail hearing on Thursday, Nightingale said. A preliminary hearing scheduled for Friday will probably be waived, he said.

The Associated Press does not identify victims of possible sexual abuse.

The girl lived in a house filled with animosity and hostility, and her parents traded bitter allegations of physical harm and child-abuse in recent years. Booth and his estranged girlfriend Michelle Fazek threatened each other and applied for protection-from-abuse orders against each other, according to court records.

"There was a lot of strife in the house before and after separation," said Bruce S. Gelman, an attorney who had represented Booth.

"I believe these two people hated each other at some point," Gelman said. "The ability of the two parents to cooperate in custody was dysfunctional. Somebody was always being accused of violating the custody order."

The girl initially told police two masked men came to the house in Elizabeth Township, about 20 miles southeast of Pittsburgh, and killed her father, said James Morton, assistant superintendent of Allegheny County police.

"It didn't take her long to get off of that (story)," Morton said.

She then admitted that she killed him, authorities said.

Fazek told The Associated Press that the girl had been abused and that she complained several times to county child welfare officials that her daughter and son were living in squalor with Booth. Police officers who found Booth's body said conditions in the house were deplorable.