The murder trial of a convicted Massachusetts fraudster accused of killing his wife after learning of an affair kicked off Monday, with prosecutors delivering an opening statement that began shortly before 10 a.m.

In a surprise move during jury selection last month, Brian Walshe, 50, pleaded guilty to lesser charges of misleading a police investigation and improper conveyance of a human body.

He is still facing a first-degree murder charge that could land him in prison for life with no chance of parole if convicted.

He is accused of killing and dismembering his 39-year-old wife, Ana Walshe, whose remains have not been found. However, according to Walshe’s defense, he found his wife dead in their bed, “nudged” her, and she fell lifeless to the floor. Then he hid her remains and lied about it.

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Defense attorney Larry Tipton told jurors in his opening statement that Walshe “nudged” his wife in bed and discovered she was dead.

“Now he was panicking, and he doesn’t understand what has happened and what is happening,” Tipton said. “It didn’t make any sense to him. It didn’t make sense that somebody he had just been with, and enjoyed New Year’s Eve with into New Year’s Day, would suddenly be dead.”

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Tipton said evidence would show a “sudden, unexplained death” and that such a thing “happens.” He denied the prosecution’s allegation that his client was aware of Ana’s suspected affair with a friend from Washington, D.C., where she commuted to work.

“Brian Walshe is not a killer,” he concluded.

She was last seen on New Year’s Day in 2023, and prosecutors allege her husband dismembered her in their Cohasset, Massachusetts, home before hiding her remains. She was reported missing days later by her boss.

Cohasset Police Sgt. Harrison Schmidt, who responded to take the missing person report, was the first witness.

With Schmidt on the stand, prosecutors played recordings of Walshe’s initial interviews with police, in which he acknowledged marital trouble stemming from his art fraud conviction and his inability to move with the family to Washington, where he said his wife was making $315,000 a year.

Schmidt testified that he checked the trunk of Walshe’s Volvo SUV and saw it was covered with plastic sheeting. The detective said he returned to the Cohasset police station and put a tracker on Ana’s passport. He also showed photos taken during a walkthrough of the home, which showed Walshe was sleeping in a separate bedroom that had a hole in the ceiling.

Prosecutors have alleged that police recovered evidence from a dumpster near Walshe’s mother’s house, including a rug from the family home, clothing and a COVID vaccination card belonging to the victim, a hatchet, a hacksaw and red and brown stained towels.

Prosecutors have laid out two potential motives in the case. The first is that Walshe allegedly discovered an affair between his wife and another man, whose name he is accused of searching on Google six times. The second is that he allegedly believed being the sole caretaker of their children would help him avoid prison in connection with a federal art fraud case.

And he was the beneficiary of her $2.7 million life insurance policy.

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Investigators say they found digital evidence showing Walshe allegedly searched Google more than a dozen times for instructions on how to dispose of human remains. Then they say they found video of him at Home Depot, buying mops, goggles and a knife.

The trial before a jury of nine women and seven men is expected to last two to four weeks. 

Schmidt is expected to return to the witness stand Tuesday, but prosecutors said they were already running ahead of schedule.