The filing also points to messages allegedly sent by Proctor, in which he referred to Read as a "retarded," "whack job c---," with "no a--."
The text messages also include a slew of alleged derogatory remarks toward Boston Mayor Michelle Wu and New England Patriots owner Robert Kraft, referring to Wu as a "little c----" and Kraft as a "terrible c----- Jew."
"Put simply, they were then and are now completely and unquestionably unfit to hold positions of authority with MSP and CPD, much less to play important roles — or in Ms. Read's case, the primary role — in homicide investigations," the court filing added.
In a statement released to the media, attorneys Alan Jackson, Damon Seligson and Aaron Rosenberg alleged the two law enforcement agencies fostered "a culture of bias and corruption that they built, tolerated, and hid from the public for years."
"Michael Proctor and Sean Goode did not slip through the cracks; they are emblematic of the failure to responsibly exercise the trust and faith the public puts in these institutions," the attorneys added.
Read was acquitted of murder and manslaughter charges last year following a mistrial in the death of O’Keefe.
In a statement to Fox News Digital, MSP Col. Geoffrey Noble condemned the alleged comments made by Proctor.
"These disturbing messages are entirely inconsistent with any basic standard of decency and certainly with the expectations of a Massachusetts State Trooper," Noble said. "These racist, sexist and abhorrent comments absolutely do not reflect the values of the Massachusetts State Police and are not tolerated within our ranks. They underscore and fully support my decision to terminate Michael Proctor."
"We do so keenly aware of the ways in which this misconduct harmed the public trust on which our mission depends," he added.
At the time, prosecutors alleged Read drunkenly struck O’Keefe with her SUV and left him to freeze to death in the snowy front yard of a friend’s home in nearby Canton. However, her defense team successfully argued that Read was not responsible for O’Keefe’s death.
The development comes just days after Goode, who responded to the scene of O’Keefe’s death and testified in Read’s first trial, resigned from the Canton Police Department following an investigation into alleged misconduct, Proctor was fired from his position within the state police after his text messages sent about Read were read in her first trial.
Read is also facing a wrongful death lawsuit filed by O’Keefe’s family, and has filed a federal civil rights lawsuit against multiple witnesses who testified against her in both murder trials.
"Karen Read was acquitted of every charge related to John O'Keefe’s death — and now the agencies that negligently permitted virulent misogynists and bigots to target her will answer for what they built, what they concealed, and what they did to her," Read's attorneys wrote. "The days of hiding behind badges and promotions while peddling vile bigotry are over. The truth is coming, and with it an unflinching reckoning."
Fox News Digital reached out to the Town of Canton, Massachusetts State Police and Read’s attorneys for comment.