James Olsen, LI murder suspect, thought killing mom was 'doing something good,' expert testifies

James Olsen was so depressed while caring for his bedridden mother that he decided to take his life and hers so she didn't end up in a nursing home after he was gone, a witness testified at the Garden City man's trial Friday.

"I think he thought that he was doing something good," forensic psychologist N.G. Berrill said. ". . . He was going to relieve his own misery, and he wasn't going to leave his mother behind."

Olsen strangled his mother with a necktie before a failed suicide attempt in April 2011.

Olsen, 59, faces up to 25 years to life in prison if convicted of second-degree murder. His lawyer, Paul Delle of Garden City, has put forth an insanity defense and doesn't deny his client killed Ruth Olsen. She was 88 and had Alzheimer's disease.

But prosecutors in Nassau County Court say the defendant intended to kill his mother, and have alleged he didn't want her to find out how much of her money he was spending.

Berrill, director of The New York Center for Neuropsychology & Forensic Behavioral Science, said Olsen suffered from major depression and anxiety disorder and couldn't understand his actions were wrong.

The defense witness said Olsen had been unemployed for years and spent every day caring for his mother, becoming socially isolated, overburdened and obsessed with the idea he was mismanaging her money.

During cross-examination, Berrill said Olsen told him his brother visited their mother several weeks before the slaying. The visit was really a few days before she was killed, his brother previously testified.

Berrill couldn't recall Olsen telling him that aides sometimes came to the home to help out. And he said that Olsen told him that after strangling his mother, he ate breakfast before attempting suicide.

Assistant District Attorney Christine Geier also asked Berrill about a 2013 New York Times article when he talked about being a trial witness and how he tells his students "there's less science in there than there is showmanship."

When she asked if his testimony Friday was science or showmanship, he said he explained his clinical opinion in a serious way.