DEDHAM, Mass. — The jury began deliberating Friday in the second murder trial of Karen Read, who is charged with killing her Boston police officer boyfriend in a case that has generated more than three years of heated debate.

Deliberations began after both sides presented their closing arguments on the 33rd day of the trial.

Read, 45, is accused of striking John O’Keefe with her car outside a suburban Boston house party and leaving him to die in the snow in January 2022. She has been charged with second-degree murder, manslaughter and leaving the scene.

Read’s lawyers say O’Keefe, 46, was beaten, bitten by a dog, then left outside a home in Canton in a conspiracy orchestrated by the police that included planting evidence against Read.

Read’s second trial followed similar contours to the first, which ended in a mistrial last year.

Judge Beverly Cannone, who also oversaw the first trial, gave the jury their instructions Friday afternoon. Read has never been jailed for O’Keefe’s killing. She did not testify at her first murder trial or this one.

Defense attorney Alan Jackson began his closing argument by repeating three times: “There was no collision.” He told the jury that Read is an innocent woman victimized by a police cover-up in which law enforcement officers sought to protect their own and obscure the real killer.

He also reminded the jury Read is innocent until proven guilty beyond a reasonable doubt and a moral certainty.

Jackson suggested Brian Higgins, a federal agent, was agitated at a bar after Read didn’t respond to his text, and coaxed O’Keefe over to the Canton house party. Higgins had exchanged romantic text messages with Read and sent her a text message that said “um well” after seeing her with O’Keefe. He also gestured at O’Keefe while looking agitated, Jackson said.

“What happened inside that house, that basement or that garage? What evidence was there for investigators to look into? What did they ignore?” Jackson asked, noting the “obvious dog bites” on O’Keefe’s arm and the head injury from his falling backward onto a hard surface.

Jackson also referenced the medical examiner’s testimony in making the argument that O’Keefe wasn’t hit by the SUV. She testified that she couldn’t determine the manner of death to a reasonable degree of medical certainty.

Prosecutor Hank Brennan opened his closing argument by saying Read callously decided to leave O’Keefe dying in the snow, fully aware that he was gravely injured. He described that decision as “a choice” to let O’Keefe die.

He also said Read was well beyond the legal alcohol limit when she drove at the time.

“She was drunk, she hit him, and she left him to die,” Brennan said.

Describing O’Keefe as a “good man” who “helped people,” Brennan said O’Keefe needed help that night and the only person who could lend a hand – call 911 or knock on a door – was Read. Instead, she drove away in her SUV.

Brennan said the defense’s characterization of Higgins’ behavior at the bar earlier in the night as inaccurate. He said Higgins was “playfighting” and not displaying true hostility.

Brennan also characterized O’Keefe and Read’s relationship as failing at the time of O’Keefe’s death, and said there was growing animosity between them.

He leaned hard into Read’s own words, playing video clips of Read telling an interviewer after the first trial that she shouldn’t have been driving and how she wondered if she might have hit him. He also played angry voicemails she sent to O’Keefe that night after she arrived home.

Jackson described the investigation into O’Keefe’s death as botched and biased from the very beginning.

He attacked the lead investigator in the case, Michael Proctor, reading aloud some of his offensive and sexist texts and explaining how he was fired for his “blatant bias” in the investigation. He also noted that the state never called Proctor as a witness in this trial, as they did during the first trial.

“Michael Proctor is clearly radioactive,” he said.

Jackson also suggested Proctor planted glass on the SUV’s bumper, noting it didn’t match the cocktail glass. “That glass had to be placed there.”

Jackson also said Proctor failed to interview many key witnesses, including a snowplow driver and Brian Nagel, who had come to pick up his sister.

He said investigators never searched the house owned by former Boston police officer Brian Albert for a “sign of struggle” nor did they go there to collect blood or DNA. He also noted a group text after O’Keefe was found where one person suggested they say no one came into the house and Albert responded “exactly.”

“That is not justice folks. That is pure favoritism,” he said.

Jackson also noted the family dog, Chloe, who the defense allege bit O’Keefe disappeared and then was “gotten rid of altogether.”

“Who gets rid of their family pet unless they have something to hide?” Jackson asked.

Brennan said the data on Read’s Lexus proved she reversed her car to where O’Keefe was standing and that health data on his phone showed he had gotten out of her car right before the alleged collision.

Brennan has repeatedly referenced the data to make his case.

Read, he said, “decided” to put the car into reverse and “decided” to accelerate toward him after the two had an argument on the way to the house where the party took place.

“I suggest to you that is second-degree murder,” he said.

Brennan said the collision caused so much damage to Read’s taillight that it left a “debris field” on the lawn.

As Read arrived back at the scene the in the morning, Brennan described how she screamed “let me out” as the vehicle reached the home where the party took place.

“She knows where he is. She knows exactly where he is. She knows where she left him,” he said before playing a video clip in which Read described seeing O’Keefe in the snow and looking like a “buffalo on prairie” and a “weird shaped lump.”

Read waved to supporters as she arrived at court. About 100 supporters of Read, many of them wearing pink, were behind a barricade across from the courthouse.

William Read, the father of Karen Read, walked toward court and also waved to her supporters across the courthouse.

Whittle reported from Scarborough, Maine. Associated Press writer Kathy McCormack contributed to this story in Concord, New Hampshire.