As a Blaine man's murder trial opened Wednesday, his attorney conceded that he shot his wife a year ago, but insisted he didn't plan it.

"It wasn't premeditation," attorney Jennifer Pradt told the Anoka County jury. Gary Tomassoni, 48, had diabetes and had past kidney and pancreas transplants, she said, that left him with huge emotional pressures on top of financial strains from heavy gambling.

Helen Tomassoni, 45, was shot in the head in the couple's bedroom on July 21, 2007. When gunshots awoke the couple's 14-year-old son about 5 a.m. that morning, Tomassoni told him to call 911 because an intruder had hurt his mother.

Tomassoni faces a first-degree, premeditated murder charge that carries a sentence of life without parole. If convicted of second-degree intentional murder he could serve up to 40 years in prison.

Prosecutor Heather Pilon said Tomassoni planned to shoot his wife because he had big gambling debts coming due and he was the beneficiary of her $500,000 life insurance policy.

Pilon noted that the blue latex gloves that Tomassoni wore during the shooting were found in his basement file cabinet, along with the handgun he used and his wife's $500,000 life insurance policy. Police discovered keys to the cabinet in a pair of bloody male shorts found unwashed in the home's washer.

Tomassoni, who was unable to work much because of his medical problems, had lost more than $600,000 in casinos since 2004 and owed another $250,000 to friends and others, Pilon said. A payment on his debt was due 10 days after his wife was shot, she said.

"The defendant, in his desperation, did the unthinkable and shot his wife, Helen Tomassoni, two times in the head," Pilon told the jury.

The jury heard the 911 tape of the teen saying he thought someone was in their house. Then his father took the phone and yelled hysterically for help because shots were fired and his wife was hit. "I think they came in through the basement," he said, sobbing and whimpering.

"Do you have any idea who did it?" the dispatcher asked.

"I don't know what is going on," Tomassoni yelled back.

Judge Ellen Maas said the trial is expected to take six weeks.

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