DEDHAM, Mass. — A crash reconstruction expert who on Tuesday provided jurors his analysis of Karen Read’s vehicle the night her Boston police officer boyfriend was killed is expected back on the stand Wednesday in the 45-year-old Mansfield woman’s murder retrial.
Read is accused of striking John O’Keefe with her Lexus SUV and leaving him to die alone in a blizzard outside of a house party in Canton at the home of fellow officer Brian Albert following a night of drinking.
Day 22 of witness testimony started at 10 a.m., a little later than usual, with Judson Welcher of the accident reconstruction, biomechanics and digital forensics company Aperture LLC returning for a second day of questioning.
Welcher is believed to be the prosecution’s final witness before the case is turned over the defense.
Dr. Welcher says he's been inundated with emails from what he calls "internet trolls" including one with a subject line referring to a job.
— Ted Daniel (@TedDanielnews) May 28, 2025
Had a feeling this would come up:
— Ted Daniel (@TedDanielnews) May 28, 2025
RA: Are you familiar with a Massachusetts state trooper named Joseph Paul
JW: yes
RA: On November 5th of 20, 2024, your firm aperture was paid $44,500 by the Norfolk County District Attorney's Office to conduct work that was at least similar…
Brennan is attempting to get ahead of ARCCA with his final questions for Dr. Welcher.
— Ted Daniel (@TedDanielnews) May 28, 2025
HB: do you have an opinion to a reasonable degree of engineering certainty whether the absence of lower body breaks to Mr. O'Keefe is consistent with the defendant's Lexus impacting in a…
Good morning from day 22 of testimony in the Karen Read re-trial. We are underway with Dr. Welcher (prosecution ax recon) back on the stand. I'm an alternate and hoping to get in shortly.
— Ted Daniel (@TedDanielnews) May 28, 2025
A couple of filings from Hank Brennan.
1. Brennan wants Shanon Burgess' resume that… pic.twitter.com/GXeLxAfv5y
Before the jury was brought in Tuesday, Welcher took the stand for a last-minute voir dire — a process used to determine his competency and the evidence he planned on discussing.
Specifically, Read’s defense attorneys pressed Welcher on changes made to a PowerPoint presentation Welcher was expected to give to the jury. Welcher said he “removed a couple words” from some of the slides and had talked to prosecutor Hank Brennan, who suggested edits to the presentation.
Welcher added that he also amended the PowerPoint after his colleague, Shanon Burgess, found “better data” surrounding when Read was maneuvering her SUV on the night O’Keefe died.
Read’s lawyers had previously attempted to block Burgess’s report from being presented to jurors and Aperture experts like Welcher from testifying. They accused the prosecution of committing a pretrial discovery violation. But Judge Beverly Cannone let the prosecution proceed.
Much of the trial has focused on broken taillight pieces involving Read’s SUV, but the prosecution’s latest focus has been on the forensic experts who have analyzed data pulled from the vehicle and O’Keefe’s phone in an attempt to map out exactly where Read’s SUV was the night her boyfriend died.
Specifically, the prosecution has brought in experts to discuss a secure digital card on a circuit board of Read’s SUV modules that was not found in the initial investigation. The card details time-stamp data about when the vehicle was powered on and off, both before and after O’Keefe’s death.
When the Lexus is powered on, an internal clock begins running like a stopwatch. When the car performs a maneuver like a three-point turn or backing up, a time stamp is created.
According to Welcher, Read’s SUV made a three-point turn and then backed up roughly eight minutes later. Welcher said Read must have had “three quarters of a full throttle” on the gas pedal when the vehicle moved more than 50 feet (15 meters) in reverse the night O’Keefe died.
Welcher also showed video of him reenacting how O’Keefe may have been hit by Read’s SUV. Welcher said he did so after learning he was the same height and similar weight as O’Keefe.
The video shown to the jury included Welcher standing behind a similar type vehicle that had blue paint on the taillight. When the vehicle backed up, Welcher said blue paint ended up on his arm in the same areas where O’Keefe had injuries. However, Welch cautioned that “small changes in the pedestrian position gave you huge change in the output.”
Prosecutors allege Read intentionally backed into O’Keefe after she dropped him off at a house party and returned hours later to find him dead. The defense has claimed that she was a victim of a vast police conspiracy and that O’Keefe was fatally beaten by another law enforcement officer at the party.
A mistrial was declared last year after jurors said they were at an impasse and deliberating further would be futile.
Read has pleaded not guilty to charges of second-degree murder, manslaughter while operating under the influence, and leaving the scene of a crash resulting in death.
Get caught up with all of the latest in Karen Read’s retrial.
Reporting from the Associated Press was included in this article.
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