MINEOLA, N.Y. (CBSNewYork/AP) — A Long Island man who was convicted of strangling his elderly and sick mother with a necktie while she slept was sentenced on Monday to 17 years to life in prison.

James Olsen, 60, was sentenced by Nassau County Court Judge Angelo Delligatti for the 2011 killing of his mother, Ruth, in their Garden City home.

“This tragedy isn’t over Mr. Olsen, but I hope that you find some peace,” judge Delligatti said after imposing the sentence.

Prosecutors said Olsen methodically planned the crime, even picking out the necktie the night before she was killed.

But defense attorney Paul Delle said Olsen had been hearing voices telling him to commit suicide in the weeks leading up to the killing. He said Olsen spent years caring for his mother and thought he had to kill her first because he perceived there would be no one to care for her after he died.

Delle previously said his client “lacked the capacity to appreciate his conduct.”

After the killing, Olsen attempted suicide before calling 911, authorities said. A recording of the call was played for jurors.

“I’m just crazy. I have to be crazy,” Olsen told an operator.

Prosecutors said Olsen’s mother was found with the tie still around her neck in her bedroom, while Olsen was found in another bedroom with self-inflicted slash wounds to his neck and wrists.

In May, a jury rejected an insanity defense and convicted Olsen of second-degree murder after five hours of deliberations, Nassau County District Attorney Kathleen Rice said.

“Every senior deserves to be cared for in their twilight years in an environment free from violence, with dignity, love, and respect,” Rice said. “This tragedy could have been averted if Mr. Olsen had just reached out for help instead of lashing out against his ailing mother.”

Judge Delligatti denied a defense motion to set aside the verdict. Delle said he plans to appeal.

Following the guilty verdict in May, Olsen’s brother, Steve, said their mother would have been “horrified” by the jury’s decision. “I believe my mother forgave him as it was happening,” he said.

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