A Massachusetts woman is on trial again for the death of her police officer boyfriend, after a jury was unable to reach a verdict in the initial murder trial last year.

Karen Read is accused of killing her boyfriend, John O’Keefe, a Boston police officer, in January 2022. The prosecution alleges that, following a night of drinking in Canton, Read struck O’Keefe with her SUV outside of a private residence, then left the scene. An autopsy found that he died of hypothermia and blunt force injuries to the head.

Read’s defense attorneys have long centered on allegations that the defendant was the subject of a cover-up.

Read has maintained her innocence. She pleaded not guilty to charges including second-degree murder, vehicular manslaughter while operating a vehicle under the influence of alcohol and leaving the scene of a collision causing death.

During opening statements Tuesday in Norfolk County Superior Court in Dedham, special prosecutor Hank Brennan focused on numerous accounts Read has given in interviews with the media, in which he claims Read makes a series of “admissions.” Brennan announced his intent to present Read’s numerous statements to the media as important evidence in the Commonwealth’s case.

“You are going to hear from her own lips, and many of her statements, her admissions to her extraordinary intoxication. Her admissions to driving the Lexus. Her admissions to being angry at John that night,” he said.

Brennan directed the jury’s attention to a clip of the defendant’s interview from October 2024.

“I didn’t think I ‘hit him,’ hit him,” Read said in the interview. “But could I have clipped him, could I have tapped him in the knee and incapacitated him?”

Karen Read talks with her defense team during her second murder trial at Norfolk Superior Court, April 22, 2025 in Dedham, Mass.

Stuart Cahill/The Boston Herald via AP

Brennan told jurors they will see a host of video and DNA evidence during the trial, including what he said is DNA of O’Keefe’s hair recovered from Read’s bumper.

He also pointed to evidence pulled from Read’s Lexus, which he said will show that the defendant’s vehicle reversed at least 70 feet around the time of the alleged murder. Brennan repeatedly highlighted the broken taillight identified on the defendant’s vehicle as evidence that her Lexus struck O’Keefe.

Defense attorney Alan Jackson asserted in his opening statement that Read did not cause the death of O’Keefe.

“There was no collision with John O’Keefe,” Jackson repeated three times.

Jackson said the assertion that O’Keefe was struck by Read’s Lexus SUV is “contrary to science.”

“John O’Keefe did not die from being hit by a vehicle, period,” Jackson said.

Jackson promised to show the jury that the police investigation on which the Commonwealth has based its case is “riddled with errors.”

He made numerous references to personal relationships that investigating officers held with witnesses in this case, including Boston police officer Brian Albert, who owned the residence where O’Keefe was found dead on the lawn.

The attorney also criticized the involvement of former Massachusetts State Police Trooper Michael Proctor, the lead investigator in the case. Jackson introduced Proctor as “a longtime family friend of the Alberts who has been disgraced by his own agency,” alluding to his dismissal by state police.

“You’ll see from the evidence in this case that this case carries a malignancy, one that is spread through the investigation,” Jackson said. “It’s spread through the prosecution from the very start, from the jump, a cancer that cannot be cut out, a cancer that cannot be cured, and that cancer has a name. His name is Michael Proctor.”

The attorney promised to show the jury personal text messages between Proctor and his high school friends, in which he made vulgar and sexist comments about Read. Jackson then alleged that Proctor admitted in the same text conversation to seizing the defendant’s cell phone without her permission and searching her phone for nude photos.

Proctor’s family responded to Jackson’s opening statement, calling it “yet another example of the distasteful, and shameless fabrication of lies that embodies their defense strategy” in a statement to ABC Boston affiliate WCVB.

“Jackson is under no oath to tell the truth; he does not have to speak in truths,” the statement continued. “The defense team continues to do anything to deflect from facts of the case and continues to use inappropriate analogies like casting someone as a cancer. We wholeheartedly believe the truth will prevail in this case, and justice for Officer John O’Keefe and his family will be achieved.”

Karen Read arrives with her lead defense attorney Alan Jackson, left, for her trial at Norfolk Superior Court, April 22, 2025, in Dedham, Mass.

The Commonwealth’s first witness, Timothy Nuttall, a Canton firefighter and paramedic who administered medical aid to O’Keefe, testified that he heard Read say, “I hit him,” at the scene.

“She said, ‘I hit him, I hit him, I hit him,'” Nuttall said. “I remember it very distinctly.”

In his cross-examination, Jackson focused on the witness’ ability to accurately recall details from that morning.

Jackson pointed to an inconsistency between Nuttall’s testimony in Read’s first trial, where he stated that Read said, “I hit him,” twice, and his statements Tuesday in court, where he now claims she repeated the statement three times.

“So your memory is clearer today, now, as you sit here, than it was a year ago, when you testified it was two times?” Jackson asked.

“Yes, sir,” Nuttall said with a nod.

The next witness, Kerry Roberts, testified that she saw Read point to an abnormality in the taillight of her SUV the morning that O’Keefe was found and that she recalled seeing a piece missing.

Roberts will resume her testimony on Wednesday. The trial is expected to last six to eight weeks.

Hours before the proceedings began on Tuesday, roughly two dozen protesters supporting Read gathered near the courthouse. Judge Beverly Cannone ordered a 200-foot no-protest zone around the courthouse in the interest of ensuring a fair trial.

A man “lingering and filming” within the buffer zone was arrested Tuesday morning after police say he ignored multiple requests to leave the zone, Massachusetts State Police said. The Arlington man was expected to be arraigned Tuesday on a trespassing charge, police said.

ABC News’ Nadine El-Bawab contributed to this report.