Jurors in Karen Read's second murder trial watched a test dummy get struck repeatedly by an SUV Friday as a crash reconstruction analyst testifying for the defense contradicted previous testimony about her vehicle and her boyfriend's fatal injuries.

Read, 45, is accused of fatally striking Boston Police Officer John O’Keefe and leaving him to die in the snow outside another officer’s home after a night of drinking in January 2022. She's charged with second-degree murder, manslaughter and leaving the scene outside Boston.

Her lawyers say O’Keefe, 46, was beaten inside the Canton home, bitten by a family dog and then left outside as part of a conspiracy by the police that included planting evidence against Read.

A mistrial was declared last year and so far, Read’s second trial has followed similar contours to the first.

Crash expert says damage to SUV, clothing are inconsistent with collision

The defense spent Friday morning questioning Daniel Wolfe of the accident reconstruction firm ARCCA. Wolfe initially was hired by the federal government as part of an investigation into how law enforcement handled O’Keefe’s death. He testified at Read’s first trial and has since been paid by the defense.

Wolfe described conducting numerous tests, including striking a dummy arm with a replica of Read’s SUV taillight at various speeds. He also had an SUV back into both an arm suspended in the air and a full-body dummy wearing clothing that matched what O’Keefe was wearing.

In every case, he said the damage to Read’s taillight and O’Keefe’s clothing was inconsistent with striking an arm or body.

That's at odds with a prosecution expert who testified that O'Keefe's injuries were consistent with having been struck by a vehicle.

Snowplow driver says he doesn't remember seeing a body

Snowplow driver Brian Loughran, who was on his regular route during a storm early on Jan. 29, 2022, told the defense Wednesday that he “saw nothing” when he passed by the house several hours after O'Keefe was allegedly struck by Read's vehicle around 12:30 a.m.

O'Keefe was found unresponsive outside Brian Albert’s home in Canton, Massachusetts, and was later pronounced dead at a hospital. An autopsy found O’Keefe died of hypothermia and blunt force trauma.

Loughran said he passed by the house several times starting around 2:45 a.m. and could see several feet in front of him inside his trucks because of its strong lights.

On the second pass, Loughran said he did see a car parked in the road in front of the house. He said he knew Albert and his family and decided not to report the car for violating snowstorm parking restrictions as a courtesy for being a first responder.

Under cross-examination, prosecutors attempted to undermine Loughran's memory, saying that the times he provided Wednesday contradict his initial testimony during the first trial. For example, prosecutor Hank Brennan pointed out that Loughran originally said he remembered the street where O'Keefe was found blocked off by first responders around 5:30 a.m. but on Wednesday, Loughran said it was closer to 6:15 a.m.

When Brennan asked if Loughran had a “foggy” memory, Loughran said he did not — only that he had made a mistake.

Brennan also asked if Loughran had been threatened by a confrontational blogger known as “Turtleboy” to help the defense's case. Aidan Timothy Kearney, who was in the courtroom Wednesday, has advocated heavily in support of Read's innocence. He has been charged with harassing, threatening and intimidating witnesses in the case.

Loughran said Kearney never threatened him, but the blogger did call him and did not disclose he was recording the conversation. The call was later posted online.