In the final day of testimony in the Adam Thomas sentencing trial on Tuesday, an Oregon Health Sciences University psychiatrist told the court that the youth’s psychological development was stunted by the death of his father.

Dr. William Sack, a child and adolescent psychiatrist, said in Deschutes County Circuit Court that as result, Adam Thomas was unable to resist the influence of Justin Link, 20, and prevent the March 26, 2001, murder of his mother, Barbara Thomas.

Sack, a 1960 graduate of the University of Oregon Medical School, had testified in the Kip Kinkle case. The 15-year-old Thurston High School student in Eugene shot and killed both of his parents in May 1998, and then opened fire on 27 students at his school, fatally wounding two of them.

Adam Thomas’ psychological development was influenced from the time his father, Clair Richard Thomas, 69, died of cancer in June 1997, Sack told the court.

Adam Thomas was unable to develop ”inner autonomy and some self-confidence,” Sack said, and at the time of the murder was psychologically equivalent to a 13- or 14-year-old adolescent.

Sack was called to the witness stand by Dennis Hachler, one of Adam Thomas’ attorneys, as the defense opened and closed its case on Tuesday.

Earlier on Tuesday, the prosecution closed its case.

Today, attorneys will present their closing arguments, and Adam Thomas is expected to deliver a statement to the jury before it begins its deliberations.

Adam Thomas faces either life in prison or the possibility of parole after 30 years.

During a psychiatric evaluation in August, Thomas told Sack he was experiencing nightmares, sleep disturbances and ”intrusive thoughts” after seeing crime scene photos of his murdered mother, 52-year-old Barbara Thomas, Sack said. Jail personnel prescribed the 20-year-old a mild anti-depressant to help him sleep at night.

Thomas told the psychiatrist that he had suicidal thoughts as a teenager, and again over the two years following his mother’s death.

”He says he still talks to his mother and hopes she is doing well where she’s at and feels bad for what he did,” Sacks testified.

During Sack’s interviews with Adam Thomas, the youth said he felt like an outcast during his grade school years and never felt part of a social group. During his upbringing, his father was his main source of support, according to the interviews.

After his father’s death, Adam Thomas drifted apart from his mother, and was unable to discuss his grief, the psychiatrist said. He tried committing suicide once by eating a bottle of aspirin, Sack said; another time, he said, Thomas pointed a gun to his head.

”He was kind of a lost kid, so he turned to his peer group for support,” Sack said.

Adam Thomas, who Sack described as having a ”passive dependent personality,” clung to Link.

”(Justin) was free, he was a rebel, he was a tough guy, he was charismatic,” Sack said. ”Adam just kind of took to this guy.”

The youth’s relationship with Link was such that when Link suggested murdering Barbara Thomas, Sack said, Adam Thomas wasn’t powerful enough to stop the plan from coming to fruition.

Defense attorney Hachler said Adam Thomas’ psychological traits at the time explain why he may have been swept up by Link’s plan. Hachler drew parallels between the mentality of the Redmond youth and that of hundreds of people who have perished in cult suicides.

Kandy Gies, Deschutes County Deputy District Attorney, asked Sack in cross-examination if Adam Thomas was aware that what he told the psychiatrist would be discussed in court.

”He knew I would be a witness in court,” Sack said.

Gies also read from Sack’s report what Adam Thomas told the psychiatrist during their first interview in May 2001. Adam Thomas told Sack at the time that he wanted to be famous, that he was fascinated with death, that he was interested in Satanism and that ”he wanted to be his own God,” Gies read from the report.

Jason Thomas, Adam Thomas’ older brother by seven years, said in a taped interview played for the jury that his family was close-knit during the years prior to the death of Clair Thomas, the husband of Barbara Thomas.

Jason Thomas, an Army sergeant who is currently in Iraq, testified for the prosecution.

There was a 20-year age difference between Barbara Thomas and her husband, and by the time Adam Thomas was a teen, Clair Thomas was aging, and was less able to be active in Adam Thomas’ life, Jason Thomas said.

Adam Thomas favored his father, Jason Thomas said. When their father died, ”he just became a rebellious teenager,” disobeying household rules and throwing fits of rage. Adam Thomas broke a door once, Jason Thomas said. Another time he used a hammer to puncture a wall.

”He never said, I’m going to hurt you,’ or anything like that,” Jason Thomas said.

In the weeks prior to Barbara Thomas’ murder, Adam Thomas began spending less time at home. Barbara Thomas was worried her son was going to end up in jail, or worse yet, dead, Jason Thomas said. She was also concerned for her own safety after she learned her son had broken into her home.

”She never said straight out, I’m worried for my welfare,’ but I know she thought it,” Jason Thomas said.

He said on the tape he thought the five youths responsible for his mother’s death should receive equal punishments.

”My mom had 25 to 30 years left on her life,” he said. ”That’s what they should get.”

”My parents were my last link to my past,” he said. ”My kids will never know them.”

Co-defendants Lucretia Karle and Ashley Summers, 17, are serving 25 years in prison for their role in the crime. Seth Koch, 18, was sentenced to life in prison without the possibility of parole. Link has been convicted but awaits sentencing.

Lisa Rosetta can be reached at 541-617-7812 or lrosetta@bendbulletin.com.