There are reasons why a former Hawaii soldier beat his 5-year-old to death, a social psychologist testified Thursday.

Naeem Williams, facing the death penalty after being convicted of murder in his daughter's 2005 beating death, is an example of how "situational factors" can cause someone to commit a crime, said Craig Haney a professor at the University of California, Santa Cruz.

Williams' defense team is trying to convince a jury not to choose a death sentence for him. Jurors have been listening to testimony from family and friends who want Williams to instead be sentenced to spend the rest of his life in prison.

Factors that contributed to Williams' abusive actions included the physical abuse he suffered from his stepfather as a child, being in a tumultuous marriage and living in Hawaii, where he was isolated from extended family members who could have "seen danger signs and intervened," Haney said.

Williams previously testified that he beat his daughter Talia almost daily to discipline her for having bathroom accidents and because of frustrations in his marriage to the girl's stepmother.

Williams was a "decent person up until these events, and a decent person afterward," Haney said.

Haney, who was one of the researchers involved in a 1971 incarceration study known as the Stanford prison experiment, said Williams would do well if sentenced to life in prison.

He described Williams as a "model inmate" at the Honolulu Federal Detention Center, where he has counseled a fellow inmate on the importance of family and has taken classes on religion, typing and Hawaiian history and culture.

The abuse Talia suffered was "uncharacteristic" for Williams, who Haney described as "passive, almost to a fault," who had previously led a law-abiding life.

"I'm not trying to excuse it," Haney said, "I'm trying to explain it."


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