Karen Read’s defense team pulled a crash expert’s credibility by pointing out shocking spending and alleged contradictions encountered in the experiment as the state entered its 11th hour of testimony.

Read is accused of killing her then-boyfriend, Boston policeman John O'Keefe, who rammed him outside a family party on 34 Fairview Road with her Lexus SUV and died in cold temperatures shortly after midnight on January 29, 2022.

The state's expected final witness, Dr. Judson Welcher, a crash reconstructionist at Aperture LLC in Texas, firmly determined his discovery, with Read's vehicles allegedly attacking O'Keefe.

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"(O'Keefe's injury is consistent, and it also hits and touches hard ground (such as frozen ground)" Welcher told Special Attorney Hank Brennan.

On the sometimes exciting cross-examination line, Welcher often provides non-transferees to the question of defense attorney Robert Alessi, which revolves around his modifications to the PowerPoint demonstration used in the Read trial to portray Aperture's investigation.

"Suppose the trial begins on April 22, 2025," Alicy said. "Did you create an updated presentation (start) after or after?"

"I don't know," Welcher replied.

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Alessi hopes to determine when Welcher changes the document and whether the prosecutor communicates with him about the changes.

Welcher finally gave up before he testified that he first changed his speech on May 13, with the latest changes recently "about 10 minutes ago."

"Half of that was objection to the defense," Welcher said. "I had to add all the parts to where everything was. Then, when I went out here, Mr. Brennan asked me to mention evidence about statements that I would not allow. So that would have been within the last three days. Then, I made several changes based on the judge's ruling."

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But Welcher testified against cross-examination that his amendment to the speech did not change the entire document.

"I changed a slide," Welcher said. "There were 130 slides initially, or something like that. Half the change of that day was a slide. I added a line to the bottom of the previous slide."

"So, if it doesn't matter, why should it be held in the trial?" Alicy asked. "Why don't you give up on it and then discuss it with testimony?"

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"So it ended up being abandoned because it was trivial and I didn't need to have it," Welcher said. "The way it came out was exactly the way it was before May 13. So it didn't change anything."

During cross-examination, Welcher revealed that the district attorney's office had previously agreed to pay at least $325,000 for the company's services and covered the cost of the Lexus SUV used in the test.

"We kept it (the vehicle) until the trial was over," Welcher said. "We were selling it (at the time) and charging the Commonwealth the difference in the price."

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According to Alessi, Aperture's services have paid $44,510 so far, and the state is expected to pay more than $400,000 for eight months of work.

Jack Lu, a retired Massachusetts senior court judge and Boston College law professor, told Fox News Digital. "He did not directly answer Mr. Alessi's question. He may not have done it on purpose, but he is no longer a near-perfect example of how expert witnesses should testify."

Welcher testified during a direct inspection that the O'Keefe's arm injury occurred at the same time as the make and model of the Read vehicle. The crash expert pointed out a video showing him painting the taillights of the car before brushing his teeth to mimic the collision.

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Alessi hopes to raise questions around Welcher's discovery and grill a biomechanical engineer on the method behind his experiments around the cause of O'Keefe's eye injury.

"I'm trying to be clear," Welcher said. "We don't know the exact body position he's at the influence point, nor the exact position on the ground. This is part of the reason I'm not trying to fully simulate this because we don't have enough parameters to do this. So I don't have that information. I show the geometry shown by someone relative to Mr. O'Keefe's height."

"So, you don't have the proper information," Alessi said. "So, can't you stand out from the spoilers with the answer you just gave, tearing his eyes apart?"

Welcher doubled down on his investigation and claimed in the stands that although Alessi revealed in Welcher's test that the vehicle moved only two miles per hour, according to the company's information at the time, Aperture's experiment was correct, which was much lower than the speed of the Read vehicle.

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"Do you agree to your blue paint test at two miles per hour?" Alicy asked.

"Of course," Welcher said.

"You didn't do the blue paint test at 20 miles per hour, right?" Alicy said.

"That's right," Welcher said. "I'm not going to hit myself with Lexus at 20 miles an hour."

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Wednesday marked Welcher's second day testimony as the state is expected to rest in the case this week.

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“The model followed here is very good and professional,” Lu said. “What you have here is a very good judge and met a very good lawyer,” added, “and that leads to a loose, focused on secondary cross-examination. It works well here, partly because the witnesses aren’t super evasive.”