MARTINEZ -- A judge has ruled a 58-year-old woman is not guilty by reason of insanity for stabbing her 81-year-old neighbor to death in 2012, according to the Contra Costa District Attorney's Office.

Contra Costa Judge Terri Mockler issued the ruling at a hearing on Friday after Diane Sydenham pleaded guilty to second-degree murder. Instead of prison time, Sydenham will spend the remainder of her life in a state mental hospital.

Authorities said Sydenham stabbed retired psychologist James Durkin 28 times in the chest with a kitchen knife in August 2012. About three days after the stabbing, a neighbor found Durkin inside his Kensington home with the knife still in his chest.

A police detective later testified at a preliminary hearing that Sydenham's blood was found inside Durkin's home on Coventry Road, and Durkin's blood was found inside Sydenham's home in nearby Albany.

David DeBolt covers breaking news. Contact him in Richmond at 510-262-2728. Follow him at Twitter.com/daviddebolt.



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