A defense attorney for a British man accused of killing his wife and 9-month-old daughter told a jury Monday that his wife shot the baby and committed suicide, and he covered up her actions to "protect her honor."

But a prosecutor said Neil Entwistle killed his wife and daughter because he was dissatisfied with his sex life, despondent about not being able to find a job and wanted to start a new life.

Entwistle, 29, is charged with fatally shooting his wife, Rachel, 27, and daughter, Lillian Rose, in their Hopkinton home in January 2006. The judge was instructing the jurors on the law, and the panel could begin deliberations as early as Monday afternoon.

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The couple had just moved into their rented home 10 days earlier, and by all accounts, appeared to be happy and madly in love with their daughter, according to numerous witnesses who testified during the three-week trial.

But Assistant District Attorney Michael Fabbri urged the jury to consider evidence that pointed to "the two sides of Neil Entwistle," including his visits to Internet sex sites in the days and weeks before the slayings. Fabbri dismissed the defense theory that Rachel Entwistle killed her baby and herself, noting the couple had recently returned to the United States so Rachel could be near her family in Massachusetts. The couple had lived in England for several years before that.

"Why would Rachel commit suicide?" Fabbri asked.

"She was back home, she had her home, she had her car, she had her family, and she thought she had a loving husband," Fabbri said.

Entwistle's lawyer, Elliot Weinstein, said police failed to consider suicide because they immediately focused on Entwistle as a suspect when he flew home to England the day after the killings. Entwistle told police he returned home from running errands on Jan. 20, 2006, and found his wife and daughter cuddled together in bed, dead from apparent gunshot wounds.

"Neil found Rachel and Lillian dead. Neil saw that (.22-caliber gun) and knew instantly what happened, and in those moments, he knew what he had to do," Weinstein said.

Weinstein said Entwistle returned the gun to the home of his father-in-law, Joseph Matterazzo so that his wife's family would not know she had committed suicide. Police later determined that Matterazzo's .22-caliber handgun was used in the killings.

"Everything that Neil did after finding Rachel and Lillian in that bedroom, he did because he loved them," Weinstein said.

But Fabbri said the suicide theory "does not make commonsense." Holding the long-barreled gun before the jury, Fabbri said that in order to find suicide credible, the jury would have to believe that Rachel Entwistle shot her baby through the chest, had that bullet lodge in her own breast, then raise the gun over her head and shoot herself at the top of her head, just beyond her hairline.

"It could not have happened the way they said it did," Fabbri said.

Fabbri told jurors that it may be difficult for them to comprehend how a man could kill his wife and baby daughter. But he urged the jury to consider a string of failures Entwistle had had in the months before the killings.

Since moving to Massachusetts four months earlier, Entwistle had been unable to find a job, had had several Internet-based businesses fail and had been looking for sex online through Web sites for escort services and a swingers' site called AdultFriendFinder.com.

"He was failing to provide for his family, and whether that justified homicide, I am not going to stand here and tell you that makes any sense," Fabbri said.

Weinstein had Entwistle had no motive to kill his wife and daughter, and said the Web sites he visited are used by millions of people every day.

"There is no motive, no motive to kill the woman, who by everyone's account, he shared a joyful, loving and caring relationship," Weinstein said.

Jury deliberations in the Neil Entwistle murder trial will begin at 9 a.m. tomorrow morning. The panel was excused for the day after hearing closing arguments from both sides and instructions from Judge Diane Kottmyer.

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