Brian Walshe, who Is accused of killing his wife Ana Walshe on New Year's Day, hired a private investigator in December to tail her around her job in Washington, D.C., because he believed she was having an affair, according to new court filings obtained by Fox News Digital.
Walshe was cuffed and chained as law enforcement escorted him into a Massachusetts courtroom Thursday morning to stand before Judge Beverly Cannone in Dedham Superior Court for the first time since he was indicted by a grand jury last month.
The 47-year-old murder suspect was clean-shaven and wore a dark-colored jacket over a blue collared shirt and pleaded not guilty to all charges, including murder and improper disposal of a body, as well as a previous charge of impeding a police investigation.
Prosecutors allege that Walshe beat his 39-year-old wife to death in their Cohasset home and discarded her body, which investigators still have not found – an issue that presents a daunting obstacle for the state.
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There was growing tension in Brian and Ana's marriage stemming from Brian's unrelated legal troubles, which forced him to be on house arrest as part of his pre-sentencing probation for selling fake Andy Warhol paintings, according to prosecutors.
Walshe is also fighting charges that he allegedly destroyed and pillaged his father's will.
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In December, Brian suspected Ana was cheating on him, and "he would repeatedly access the Instagram page of one of Ana's male friends from Washington D.C.," the court filing says.
The day after Christmas, Brian's mother, "with his input and direction," hired a Washington, D.C.,-based private investigator "to conduct surveillance of Ana for the purpose of proving infidelity," according to the court filing, and researched divorce on Dec. 27.
At the time, Ana worked as a real estate executive for Tishman Spyer in Washington, D.C., where she spent her time during the week, before coming home to her husband and their three children on weekends.
On Dec. 28, Ana "became uncharacteristically emotional and extremely upset" while she was out with her friends in Washington, D.C., because she thought Brian was going to jail, according to court documents.
"Ana told her friend that she intended to relocate her three children to Washington, D.C. and was prepared to leave Mr. Walshe," the court filing says.
Walshe's lawyer, Tracy Miner, addressed these new revelations in court on Thursday, when she told the judge the private investigator was allegedly Walshe's mother's idea.
Miner said her client reportedly told his mother, "Go ahead. You'll be proven wrong. Ana is good."
Prosecutors revealed that Walshe would be the sole beneficiary of Ana's life insurance, which totaled about $2.7 million.
Miner addressed this point in court, as well, claiming there was nothing to suggest Brian was looking for money and alluded to the New Year's Eve party, where Brian, Ana and their mutual friend spent a "celebratory" night.
Their friend left around 1:30 a.m. on Jan. 1, which was the last time Ana was seen alive.
The legal sparring in court provided a glimpse into the battle that could play out in a potential trial.
The state reiterated Walshe's 21 alleged disturbing Google searches, which included "Ten ways to … dispose of a dead body if you really need to" and "can you be charged with murder without a body?" among several others, that started between 4:50 a.m. and 6:30 a.m. on Jan. 1, according to court documents.
The prosecution also ran down a lengthy list of cleaning supplies and rug replacements, as well as dozens of bath towels, that Walshe allegedly bought from different stores in a short period of time, and several dumpster locations where he was seen on surveillance cameras.
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Miner countered and said her client also Googled topics like making large charitable donations and best vacation spots on the same iPad around the same time and painted Walshe as a devoted caretaker and doting father while Ana was absent from their home for stretches at a time.
She also said several of the items that Walshe allegedly bought were found in the basement "untouched," according to Miner, and Brian "willfully" turned over electronic devices to police.
After the two sides presented their arguments, Walshe was ordered to be held without bail, as he has been, scheduled the next appearances for Aug. 23 and Nov. 2.
The Norfolk County District Attorney called Thursday's hearing one more step "in a long process" that will wind its way through the Massachusetts judicial system.
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Miner said in a statement to news outlets that the indictment "contains only allegations."
"It is not evidence," she said. "It will be up to the prosecution to prove those allegations beyond a reasonable doubt, which is significantly more difficult than is obtaining an indictment in a grand jury proceeding where the defense does not have the right to participate or even be present. That is why defendants are presumed to be innocent under our constitution."
Experts have expressed differing opinions on the strength of the state's case.
Iris Eytan, a high-profile Massachusetts criminal defense attorney, questioned the strength of the evidence presented court.
"I’m not saying that he’s innocent, and he’s not responsible, but I’m saying hold off on making any rash judgments," Eytan, who helped clear her client Barry Morphew of murder charges, told Fox News Digital in a previous interview.
"When they rush in, and they charge somebody with murder two weeks after the date of someone's disappearance, that's quick without having a body."
Ana's mysterious disappearance was originally investigated as a "non-suspicious" missing person case, until Brian's comments to police could not be corroborated, and he was arrested for misleading a police investigation.
While he was in jail, police gathered evidence and scoured through security footage before bringing the case to court and charging him with Ana's murder and disposing of her body.
Authorities believe Ana's body may have been incinerated.
However, prosecuting a murder without a body is difficult but not impossible, experts told Fox News Digital in previous interviews.
Massachusetts criminal defense attorney Nate Amendola stressed that there is "no direct link" between Walshe and the death of his wife.
"This is a pure circumstantial case," he told Fox News Digital in a previous interview. "There is no direct evidence because nobody saw her being killed. And there's no physical body. And there's really no physical evidence, other than some blood and some personal items."
