TRENTON, N.J. (AP) — A recently uncovered Google search for murder methods was a key factor in a New Jersey man’s decision to plead guilty this week to killing his mistress, his lawyer says.

Rosario DiGirolamo faces a 25-year prison sentence after admitting to killing 27-year-old Amy Giordano of Hightstown in June 2007 and dumping her dismembered body in a New York pond.

The Times of Trenton reports newly discovered evidence that DiGirolamo had done a Google search of the phrase “lethal karate blows to the back of the head” days before the killing convinced him to take a plea deal.

Defense attorney Jerome Ballarotto says the Google search evidence was “catastrophic.”

DiGirolamo left the couple’s 11-month-old son in the parking lot of a Delaware hospital.

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