A state trooper's "unprofessional" texts read out loud in court during the spectacle of Karen Read's murder trial opened Pandora's box.
And "there's no way to undo this," law expert Shira Diner told Fox News Digital about restoring credibility and trust.
Jurors shook their heads last week as Massachusetts State Trooper Michael Proctor, the lead investigator in the case, read his own texts that included calling Read a "wack job," a "babe … with no a--" and a "c---;" wishing she would kill herself; and joking about looking for nudes on her phone.
The optics are ugly, but the ramifications could be worse. Proctor, who works out of the Norfolk District Attorney's Office, also played a prominent role in the homicide case against Brian Walshe.
Walshe is accused of killing his wife, Ana, during an early-morning fight on New Year's Day 2023, and disposing of her body, which still hasn't been found.
The Norfolk District Attorney's Office filed criminal charges against Walshe, and Proctor is the designated case officer.
Proctor said during his testimony that the texts were "unprofessional and regrettable," as he was being pummeled by the defense's cross-examination, but stood by the integrity of the investigation.
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"It's hard for me to see how this doesn't impact this (Brian Walshe's case) and the credibility of the DA's office," Diner said.
The Norfolk District Attorney's Office declined to comment on Read's trial or potential aftermath, and the Massachusetts State Police didn't respond to Fox News Digital's requests for comment.
Diner is a lecturer and clinical instructor at Boston University School of Law and the president of the Massachusetts Association of Criminal Defense Lawyers. She's not involved in Read's or Walshe's cases.
"In some ways, this is completely unchartered," Diner said because of how detailed the texts are and how many eyes are on this particular trial.
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Read allegedly ran over her boyfriend – Boston police officer John O'Keefe – during a booze-fueled fight in January 2022 and left him to die on the front lawn during a blizzard, according to prosecutors.
She denied the allegations and alleged she was set up by the Albert family, an influential clan that owns the Canton, Massachusetts, home where O'Keefe's body was found.
Read's defense team claimed the Albert family orchestrated an elaborate cover-up using friends in law enforcement agencies and the prosecutor's office.
The murder-or-conspiracy trial fit for a TV drama became even more salacious when the Boston suburb spiraled into split allegiances. #FreeKaren billboards cropped up, and protesters and supporters clashed.
A Read supporter and controversial blogger with a loyal following – Aidan "Turtleboy" Kearney – was arrested and hit with witness intimidation charges shortly before the trial began.
He pleaded not guilty, but the arrest riled up the pro-Read base and Kearney's readers, who call themselves "Turtleriders," and poured gasoline on the fire.
"If this was a trial where no one was paying attention, the cross-examination (of Proctor) would have come and gone, and maybe a few defense lawyers would have been paying attention, but that's pretty much it," Diner said. "But now, there's no way to undo this."
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Walshe's lawyer, Larry Tipton, already took notice, and told local news outlets, like NBC 10 Boston, that he plans on filing new motions that name Proctor, as well as any other investigators implicated in Read's trial.
He said he hasn't concluded if Proctor tainted the investigation against his client, NBC 10 Boston reported.
Tipton didn't return Fox News Digital's calls for comment, and a new motion hasn't been filed yet. Walshe's next pre-trial hearing is scheduled for Friday.
As an outside legal expert, Diner said Proctor's testimony potentially sank the Commonwealth's case, and will likely impact Walshe's trial and any other case where this DA's office and Proctor are involved.
Because of credibility concerns, defense attorneys in future cases involving Proctor could move to have him impeached, Diner said.
"It's an extreme in what we're dealing with," she said. "There are police officers who are not credible, whose bias comes up all the time. That's in more cases than not.
"But the degree to which the defense lawyer has this information about actual statements this officer made is pretty rare … And what makes this even more unique is that it's so public."
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Walshe's lawyer didn't tip his hand about what motions he would file.
Diner can only speculate on what Tipton's next move could be (which she discussed in detail in the interview below).
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What's vital to know, according to Diner, is how the defense got their hands on Proctor's texts.
Did prosecutors voluntarily turn them over during discovery, or did Read's lawyers get them elsewhere? That will determine if the credibility of the prosecutor's office is tarnished, she said.
"As a criminal defense lawyer, I would have a lot more respect for the DA's office if they turned it over, if they were forthcoming," Diner said.
"But if it turns out (Read's) defense lawyer got that information … some other way, and it wasn't turned over, that's a strike against the DA's office in terms of their credibility."
Fox News Digital's Bonny Chu contributed to this report.
