Things to know about the retrial of Karen Read in the killing of her police officer boyfriend

The defense in Karen Read 's second murder trial began presenting its case Friday after the judge declined to find her not guilty.

Read, 45, is accused of fatally striking her boyfriend, Boston Police Officer John O'Keefe, 46, with her SUV and leaving him to die in the snow outside another officer's home after dropping him off at a party in January 2022. Her lawyers say she was framed in a police conspiracy and that someone inside the house killed him.

A mistrial was declared last year. Read's second trial for second-degree murder, manslaughter and leaving the scene outside Boston has so far followed similar contours to the first.

Defense tries to toss all Read's charges, unsuccessfully

Before jurors entered the courtroom Friday, defense attorney Alan Jackson asked the judge to acquit Read of all charges. It's a routine motion that's nearly always denied, but offers hints at key themes for closing arguments.

''The commonwealth cannot and did not say or prove a collision at a particular time, a collision at a particular place, a collision with a particular person, or that a collision even occurred on January 29th, 2022," Jackson said, calling the case a ''vindictive prosecution'' that ''never should have been brought.''

Prosecutor Hank Brennan countered that the evidence of a collision was ''overwhelming,'' citing witnesses who testified Read admitted she hit O'Keefe, taillight fragments found in his clothing, and SUV data showing she reversed around the time he was allegedly struck.

Judge Beverly Cannone denied the request.

Accident reconstruction reports get a closer look

Jurors then heard from Matthew DiSogra, an accident reconstruction engineer hired by the defense who reviewed reports by prosecution's experts analyzing Read's SUV and O'Keefe's phone.

DiSogra critiqued a prosecution expert for noting how a similar SUV had a three-second delay between vehicle ignition to the infotainment system starting — but not testing Read's vehicle for the same delay.

He also testified that none of the ''trigger events'' recorded by Read's SUV the night O'Keefe died were caused by a collision. However, under cross-examination, he acknowledged he wasn't offering an opinion about whether the SUV struck O'Keefe because collisions don't trigger such data recording.

The prosecution rests

Prosecutors rested their case Thursday with a short video clip from a documentary about the case, in which Read talks about asking her lawyers whether she could have hit O'Keefe. Her legal team denies this clip constitutes a confession.

Throughout the trial, prosecutors relied heavily on physical evidence from the scene and testimony from law enforcement first responders who said they heard Read repeatedly say ''I hit him'' after she found O'Keefe.

Defense questions a forensic expert's methods

Judson Welcher, an expert with the forensics company Aperture LLC, testified Wednesday to the prosecution that damage to Read's SUV was ''consistent with a collision'' involving O'Keefe if the vehicle was moving faster than 8 mph (13 kph). Welcher returned to the witness stand Thursday and faced cross-examination.

Under cross-examination, defense attorney Robert Alessi pressed Welcher about the $325,000 the state is paying his firm for its analysis and challenged his decision to cite a 1979 study in a PowerPoint presented to jurors the day before. The study says head injuries were the most common in pedestrian crashes, but Alessi asked Welcher if he was aware that more recent data indicates that lower-extremity injuries are more common.

Welcher said he would need to see that data.

Alessi also scrutinized Welcher's suggestion that a cut on O'Keefe's face could have come from the SUV's spoiler. Welcher based his theory on O'Keefe being at street level, not on a 4-inch berm separating the street from the yard.

''I absolutely considered the berm,'' Welcher said, adding that there wasn't enough information to determine where exactly O'Keefe had been standing that night.

The back-and-forth questioning stretched throughout Wednesday and into Thursday, with Alessi probing the methods Welcher used to assess cuts on O'Keefe's arm and his theory on how O'Keefe might have fallen after being struck.

On Thursday, Alessi asked Welcher to confirm that Read backed her vehicle into O'Keefe's parked vehicle when she pulled out of her driveway to search for him after he didn't come home the night of the party. Welcher confirmed that the vehicles touched.

Prosecutors have pointed to Read's broken taillight as evidence she hit O'Keefe with her vehicle. Read's defense team has attempted to show the taillight could have been damaged another way.