Crash expert analyzes experiments he conducted with SUV similar to Karen Read’s

DEDHAM, Mass. — Only one witness was called to the stand Tuesday, the start of week 6 in the retrial of Karen Read.

The witness was Dr. Judson Welcher, an accident reconstructionist who said he bought an SUV similar to Read’s to conduct experiments.

Welcher told the jury that John O’Keefe was struck by Read’s Lexus.

In one of his tests, Welcher played the part of O’Keefe using a 2021 Lexus he purchased.

Welcher told jurors the wounds on O’Keefe’s right arm line up with shards on Read’s broken taillight.

“Even a two mile an hour impact redirects me back and causes me to rotate,” Welcher explained.

Video played in the court room showed Welcher being hit by the SUV.

Read pushed back against his testimony.

“He tried to dress identically to John, but didn’t do anything else to mimic what the Commonwealth is accusing me of,” she said.

Welcher also analyzed data from Read’s Lexus, which recorded a sudden acceleration in reverse outside 34 Fairview Road at 12:31 a.m., but did not record a collision.

“The Lexus is a 6,000 pound vehicle,” Welcher said. “Mr. O’Keefe is, like, 216 pounds. So it’s not going to register from hitting a pedestrian.”

“Recreate that for us,” Read said outside of court. “Back up into the crash test dummy at 24.2 miles an hour in the arm and see what happens.”

Read had her own crash reconstructionist who testified in the first trial. They concluded the exact opposite of Welcher, and the jury is expected to hear that testimony later in the trial.

The trial will resume on Wednesday morning.

The prosecution in Karen Read’s murder retrial could rest its case this week after the 45-year-old Mansfield woman said last week that she believes they have just one witness left to call to the stand.

This is a developing story. Check back for updates as more information becomes available.

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