Today will be the third day of testimony in the Karen Read murder case.

Read, 44, of Mansfield, was indicted June 9, 2022, on charges of second-degree murder, motor vehicle manslaughter and leaving the scene of a collision causing death.

She is accused of running down John O’Keefe, a 16-year Boston cop and her boyfriend of two years, with her Lexus SUV shortly after midnight on Jan. 29, 2022. The pair had been at two Canton bars — first C.F. McCarthy’s and then the Waterfall Bar and Grill across the street — with others during the night and were invited to meet up at 34 Fairview Road in Canton, the then-home of Boston Police Sgt. Brian Albert.

The trial opened in Norfolk Superior Court in Dedham on Monday with opening arguments from both sides.

Prosecutor Adam Lally in his opening described a failing relationship rife with jealousy, arguing that negative atmosphere set the stage for O’Keefe’s death. He included descriptions of hard evidence, saying that investigators found pieces of Read’s Lexus SUV’s busted tail light, had determined the car went in reverse some 60 feet at 24.2 mph — enough to kill someone — and had found pieces of a cocktail glass like the one O’Keefe was drinking from embedded in the SUV’s rear bumper.

Defense attorney David Yannetti said that the whole thing was a frame job and that the investigators in the case were corrupt and personal friends of the homeowner.

“Karen Read was framed. Her car never struck John O’Keefe. She did not cause his death, and that means that somebody else did,” Yannetti said at the start of his opening.

On Tuesday, jurors heard from first responders, including the Canton Fire Department paramedic who testified that he heard Read say “I hit him, I hit him, I hit him” as she paced frantically around O’Keefe’s body on the front lawn of 34 Fairview Road.

Canton Police officer Steven Saraf also continued his testimony from Monday and said that he heard Read make similar proclamations that appeared to take responsibility for O’Keefe’s death.

Defense attorneys challenged the memories and veracity of the claims. Defense attorney Alan Jackson proved that the winter coat paramedic Timothy Nuttall remembered O’Keefe wearing that night was actually a hooded sweatshirt and asked if Nuttall remembered what Read said as much as he remembered what clothing O’Keefe was wearing.

Jackson also demonstrated that Saraf had not included the incriminating remarks in his initial reports during the day even though he got Saraf to admit that it was definitely material he would have included in a report. The statements didn’t crop up until Saraf’s grand jury testimony months after O’Keefe’s death, Jackson said.

The case was not heard on Wednesday.

This is a developing story.