The lead Massachusetts State Police investigator in the Karen Read murder trial has been relieved from duty, officials said Monday, hours after she walked free when jurors were unable to reach a verdict. 

Trooper Michael Proctor was relieved following a mistrial in which Read was accused of killing her Boston police officer boyfriend.

“Upon learning today’s result, the Department took immediate action to relieve Trooper Michael Proctor of duty and formally transfer him out of the Norfolk County District Attorney’s Office State Police Detective’s Unit,” a statement from State Police Colonel John Mawn read in part, on Monday.

KAREN READ TRIAL COULD SINK OTHER HIGH-PROFILE MURDERS, EXPERT WARNS: ‘HARD TO SEE HOW IT DOESN’T’

Massachusetts State Trooper Michael Proctor testifies during Karen Read’s trial, Wednesday, June 12, 2024, in Norfolk Superior Court in Dedham, Mass. (Greg Derr/The Patriot Ledger via AP, Pool)

Proctor’s last day with the DA’s office will be July 7, Boston 25 News reported. Fox News Digital has reached out to the state police. 

Proctor came under fire for a series of text messages he sent regarding Read which were read aloud in court, in which he admitted on the witness stand that these messages were “unprofessional.”

In the personal texts, he called Read a “wack job,” a “babe … with no a–” and a “c—.” He also said he wished that she would kill herself and joked about looking for nude images on her phone.

Many law experts believe Proctor’s testimony sank the prosecution’s case.

The Massachusetts jury had been deadlocked for days and couldn’t come to a unanimous decision about Read’s innocence or guilt after nearly 26 hours of deliberations. 

STATE TROOPER’S VULGAR TEXTS ABOUT ‘BABE’ MURDER SUSPECT COULD AFFECT OTHER HIGH-PROFILE CASE, EXPERT WARNS

Karen Read smiles as defense attorney David Yannett speaks to reporters in front of Norfolk Superior Court, Monday, July 1, 2024, in Dedham, Mass. A judge declared a mistrial Monday after jurors deadlocked in the case of Read, who was accused of killing her Boston police officer boyfriend by striking him with her SUV and leaving him in a snowstorm. (AP Photo/Steven Senne)

Read, 44, was accused of killing her boyfriend John O’Keefe. After leaving court, she stood next to her lawyers, who said prosecutors relied on a compromised investigator. 

“We will not stop fighting,” Read’s lawyer, Alan Jackson said.

“The Commonwealth intends to re-try the case,” the Norfolk County District Attorney’s Office said within minutes of the outcome. 

O’Keefe’s body was found in several inches of snow outside the home of Boston police officer Brian Albert in January 2022. 

Prosecutors alleged Read intentionally backed into him with her SUV during a booze-infused fight and let him die on the front lawn of a Canton, Massachusetts, home during a nor’easter.

Read claimed she was framed in an elaborate cover-up to protect the Albert family, which has deep law enforcement ties.

Supporters of Karen Read gather outside the courthouse in Dedham, MA on Friday, June 28, 2024. Read is facing three charges, including second-degree murder of her Boston police officer boyfriend John O’Keefe in January 2022. (Patriot Pics/Backgrid for Fox News Digital)

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She pleaded not guilty to charges of second-degree murder, motor vehicle manslaughter while driving under the influence and leaving the scene of a collision causing injury and death. 

Jurors heard from dozens of witnesses and were presented with 700 pieces of evidence during the trial. 

Fox News Digital’s Chris Eberhart contributed to this report.