A teenage girl charged with fatally bludgeoning her adoptive mother with a claw hammer had suicidal thoughts, ran away from home and was physically aggressive in the months before the slaying, her adoptive father testified Tuesday.

The testimony came in the first day of a preliminary hearing for Heather D'Aoust, 15, who is being tried as an adult in the May 25 slaying of 56-year-old Rebecca Ann D'Aoust in their Scripps Ranch home.

James D'Aoust testified that he learned in the fall of 2007 that Heather had been cutting herself. In February, administrators at Maranatha Christian School in 4S Ranch asked the girl to find another school, and she enrolled at a charter high school, he said.

In March, Heather told her mother to take her to the hospital because she was suicidal, James D'Aoust said. The same day, the father of one of her friends called to say Heather had posted a suicide note on her MySpace page, he said.

In April, she ran away from home for five days.

James D'Aoust said in late April or early May, several weeks before his wife was killed, Heather tried to leave and he blocked the front door.

"She kicked me," James D'Aoust said. "She wanted to get by me, and we tangled. She was very physically aggressive with me."

A San Diego police officer went to the house, cuffed the girl and calmed her down, but left her at home, he said.

Not long afterward, she missed a pickup from school and was found riding a trolley, D'Aoust said.

"I believe there are two Heathers," D'Aoust said.

Through her writings, it appeared that one was detailed and aware, while the other was dissociative, angry and highly sexual, he said.

"I saw the peaceful Heather" the night before the killing, James D'Aoust said. The morning of the killing "I saw Heather Two."

James D'Aoust said he didn't have his glasses on; so he didn't know it was his wife on the floor of the kitchen until he saw Heather, who came at him with the hammer and hit him with glancing blow to the back of his head.

"I charged (Heather) because I put two and two together and realized that something had happened that was very bad," he said. "She basically was kind of in a different state. She started saying `I killed Mom."'

He said he restrained the girl and yelled for another daughter to call 911.

Rebecca D'Aoust, a San Diego Unified School District teacher and counselor, died the next day at a hospital.

After Heather was arraigned, her father said she had "more obvious flaws than we knew how to cope with." He said she needed help but was not evil.

Her lawyer, Paul Pfingst, said Heather suffers from a mental illness that predated the killing.

The defendant was 14 at the time of the attack. The D'Aoust family, which includes a third daughter who was away at college, adopted her when she was very young.

At the conclusion of the hearing, Judge Michael Wellington will rule if there's enough evidence to try the girl on charges of murder and assault with a deadly weapon.