The Massachusetts State Police lead investigator in the Karen Read case has been suspended without pay following a Monday duty status hearing.

Interim State Police Superintendent Col. John Mawn accepted the recommendation made by a hearing board to place Michael Proctor, of Canton, on unpaid leave, according to Patriot Ledger news partner WCVB.

Proctor was the lead investigator in the case of Read, a Mansfield woman accused of killing her Boston police officer boyfriend, Braintree native John O’Keefe. The trial ended in a mistrial last week.

During the trial, Proctor was questioned about inappropriate texts he had sent regarding Read during the investigation. He apologized to the jury for his “unprofessional” comments.

The State Police, who drew much public criticism throughout the trial, issued a statement after the mistrial was declared. After offering condolences to O’Keefe’s family, the agency said it was transferring Proctor out of the detective unit of the Norfolk County District Attorney’s office.

A statement by Mawn read: “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. This follows our previous decision to open an internal affairs investigation after information about serious misconduct emerged in testimony at the trial. This investigation is ongoing.”

Norfolk County District Attorney Michael Morrissey says his office plans to retry Read, who was charged with second degree murder, manslaughter while driving drunk and leaving the scene of personal injury and death.

The case has drawn widespread national attention. Read’s defense claims it was a cover-up by law enforcement and that others involved framed Read for O’Keefe’s death. Prosecutors say Read and O’Keefe had been drinking at a local bar with friends and acquaintances before they got into an argument. They say she hit him with her SUV outside the home of Brian Albert, who was hosting an after-party, shortly before 12:30 a.m.

But Read’s lawyers say Read dropped O’Keefe off at Albert’s home where he was fatally beaten inside before his body was planted on the front lawn. They say she was then framed for his death.