A social psychologist says there are reasons to explain why a former Hawaii soldier beat his 5-year-old to death.
Craig Haney of the University of California, Santa Cruz testified Thursday for a defense team that's trying to convince a jury not to choose a death sentence for Naeem Williams.
The former solider is convicted of capital murder in the 2005 beating death of his daughter, Talia.
Haney says Williams' actions can be attributed in part to abuse he suffered as a child and to being in a tumultuous marriage.
Jurors are listening to testimony from people including family and friends who say Williams' life should be spared. Jurors can decide to sentence him to death or to spend the rest of his life in prison.