TRENTON, N.J. — A 12-member jury on Thursday convicted former pharmaceutical executive Dr. Jonathan Nyce of manslaughter in the brutal slaying of his Filipina wife, Michelle Rivera-Nyce at their Hopewell Township mansion on Jan. 16, 2004.

Dr. Nyce, 55, had confessed to smashing Michelle’s head on the concrete floor of their garage but contended the killing was an accident.

The passion-provocation manslaughter verdict carries a sentence of five to 10 years in prison. Dr. Nyce also was convicted of tampering with evidence, which carries a three- to five-year term.

Dr. Nyce had faced a murder charge, which could have brought a life sentence. He did not express any emotion as the verdict was read.

Dr. Nyce’s lawyer had said the death was the result of a scuffle as his 34-year-old wife returned to home from a tryst with her lover, a Guatemalan immigrant who had once landscaped the couple’s property.

In a videotaped confession, Dr. Nyce said his wife — a beauty consultant at Macy’s — lunged at him with a stiletto. Authorities were unable to find any such weapon. The defense lawyer said investigators did not search a cosmetics bag in the victim’s car.

On Wednesday, the jury failed to reach a verdict after seven hours of exhausting deliberation that concluded with the jurors asking the judge for clarification of the aggravated manslaughter charge.

The jurors asked in particular for clarification on a section of the aggravated manslaughter instructions where Judge Bill Mathesius said, “If, in light of all the evidence, you find the defendant’s conduct resulted in a probability as opposed to a mere possibility of death, then you may find that he acted under circumstances manifesting extreme indifference to human life.”

After consulting with both the prosecution and defense lawyer Robin Lord, Mathesius offered the jury a distinction between the words “possibility” and “probability” in the charge.

“Possibility is an event that may or may not have happened,” the judge said. “Probability is an effect or result that is more likely to follow its supposed cause than not follow.”

Mathesius’ instructions explained that if the jury finds Dr. Nyce’s conduct resulted in only a possibility of death, then it must consider the lesser charge of reckless manslaughter.

The jury was instructed Monday to consider aggravated and reckless manslaughter along with passion provocation manslaughter and first-degree murder while deliberating.

In his statement with police, Dr. Nyce said he drove Michelle’s Toyota Land Cruiser from their Keithwood Court estate down the road to Jacobs Creek with his wife’s corpse propped up behind the steering wheel.

Dr. Nyce decided not to take the stand in his own defense last week, but his parents ended their silence Wednesday after learning they’d have to go through another day of deliberation.

“He wouldn’t hurt a soul, not a soul,” Dr. Nyce’s mother, Emma, said as her son paced back and forth in the background. “He was always excellent to Michelle.”

The Trentonian said Emma Nyce talked about how her son gave Michelle everything she needed, and how he rescued her from her impoverished life in the Philippines.

“She got everything she wanted,” said Emma Nyce, noting her son’s three children spend an hour every night talking with their father on the telephone.

Dr. Nyce’s parents say his three children ask for their father to come home every day, but rarely mention Michelle.

“She wasn’t around much that last year,” Dr. Nyce’s father, also named Jonathan, said. “Jonathan had to take care of them all the time.”