Commonwealth v. Read — Trial ArchiveJudson Welcher
Testimony Impact
Judson Welcher is a forensic engineer and accident reconstructionist with more than 30 years of experience and ACTAR accreditation, hired by the Commonwealth through Aperture LLC. His Trial 2 testimony covered vehicle data, photogrammetry, impact biomechanics, and tail-light damage. He testified that Read's vehicle data and damage were consistent with a collision at about 12:32 a.m. and, separately, that O'Keefe's injuries were consistent with being struck by a physically identical Lexus and then contacting a hard surface. He said an impact above approximately 8 miles per hour would likely break the tail-light lens; the court did not permit him to opine that Read's specific Lexus collided with O'Keefe, leaving that as a prosecution theory or jury inference.
Challenges & Responses
What attorneys challenged during examination and how the witness responded.
Welcher's credibility was challenged on multiple fronts: Alessi established that Aperture held a contract authorizing over $325,000 in Commonwealth payments, that Welcher modified his PowerPoint multiple times during the active trial at the prosecutor's suggestion, that he did not know the model numbers of the Ring cameras used in his photogrammetry, that he assumed rather than measured the Lexus suspension height on the night of the incident, and that a confirmed low-speed collision between the Lexus and Traverse at One Meadows did not register in the TechStream data he relied upon. Welcher maintained throughout that his methodology was sound and his conclusions were reached independently.
Notable Quotes From The Record
“Mr. Brennan.”
Welcher identifies Brennan as the person who suggested unspecified presentation changes. He gave deletion of a slide referencing testimony he was not allowed to include as an example.
“I wouldn't say it's insignificant. Again, I haven't modified my PowerPoint at all. I was happy with the data I had and satisfied with the data I had. Again, once presented — as an engineer would — with better data, we use better data.”
Welcher frames the change as standard engineering practice while conceding it is not insignificant.
“You do.”
Welcher agrees with the timing sequence posed by Alessi: under the revised range, part falls after the device lock. Elsewhere, Welcher disputed that the change was consequential and maintained the original timing was within measurement variance.
“I have no dog in this fight. I don't, quite frankly, care. What I'm doing is trying to do a good engineering job, which is looking at the data and drawing sound principles and sound conclusions from the data.”
Welcher establishes his claimed objectivity and data-driven methodology for the jury.
“So from the maximum point it pulled forward to where it backed up again — that was 34 feet forward, then a total of 53 back, total travel distance of 87 feet. So went all the way forward where it stopped. It then backed up 87 feet. And when the Techstream data stopped, it's still moving. It is still moving about 23 miles an hour, and you're still at 74% throttle and 3,300 revolutions per minute on the tachometer RPM gauge.”
Key finding about the second triggering event — the Lexus was accelerating rapidly in reverse when the data window ended.
“That impact did not break or crack that tail light.”
Welcher's conclusion that the impact under discussion did not break or crack the tail light.
“The location and orientation of the laceration on John O'Keefe's right forearm and arm are consistent with the geometry and orientation of the right tail light of the Read 2021 Lexus LX 570.”
Welcher testified that the right-arm laceration location and orientation were consistent with the right tail light's geometry and orientation.
“What the data is showing is that even at a fall height as low as 40 inches onto a hard surface, you can get fairly severe skull fractures.”
Welcher testified that hard-surface falls as low as 40 inches can produce severe skull fractures.
“It is consistent with a collision as long as it's greater than approximately 8 miles an hour.”
States the greater-than-approximately-8-mph condition for his consistency opinion.
“That it is consistent with being struck by a Lexus and ultimately contacting a hard surface such as frozen ground.”
Core prosecution opinion linking O'Keefe's injuries to a vehicle strike followed by ground impact.
“So, when you have glancing contacts, you can have much higher speeds without a lot of damage to the car because you're only in momentary contact and it's a glancing type hit.”
Explains the biomechanical basis for limited vehicle damage despite a potentially injurious impact.
“Yes, you could definitely have this type of impact and not have anything beyond, say, red marks to the lower extremity.”
Directly addresses the defense argument that absence of leg fractures undermines the vehicle-strike theory.
“I don't quite frankly care whether it's new or not. I just care what's in the data. Whether it's new, old, I don't care. It's not relevant to what I'm doing.”
Welcher dismisses concern about Burgess's mid-trial amended report, which Alessi uses to suggest the prosecution team was generating new analysis during trial.
“I have certainly done amended analysis. Only certain courts and certain legal systems require reports. But for example, rebuttal — analyzing testimony that comes up in court, getting trial transcripts — I very frequently have come up with new analysis during the trial.”
Welcher distinguishes amended analysis from amended reports but cannot cite a single case where he submitted an amended report mid-trial.
“Correct. We don't have that level of certainty. We have that the height and geometry matches.”
Welcher concedes he cannot say with certainty that O'Keefe's head was positioned to be struck by the spoiler, undermining the eye laceration theory.
“We don't have enough information to determine that.”
Welcher admits he cannot determine how long the arm needed to maintain contact with the tail light to produce the observed wounds — a core gap in the prosecution's injury mechanism theory.
“I did not use his report at all. It was simply limited to the use of the photo to show a different demonstrative issue.”
Directly rebuts the cross-examination suggestion that Welcher borrowed from Trooper Paul's work.
“I wanted it to be independent in my analysis.”
Establishes Welcher's intent to conduct wholly separate analysis from other prosecution experts.
“No, I wouldn't take a person like that — opinion for that.”
Welcher distances himself from the medical examiner's cause-of-death conclusions, asserting that biomechanical analysis requires different expertise.
“The important things that I was looking at are the underlined or highlighted, which is why I highlighted them.”
Welcher explained that he considered the underlined or highlighted final-diagnosis findings while distinguishing them from the separately listed cause and manner of death.
“Correct.”
Confirms that Welcher considered the highlighted portions of the autopsy report; he had distinguished those portions from cause and manner of death.
“Nope. But we have videos from both of them and scans of the scene.”
Welcher concedes he doesn't have the model numbers for either Ring camera used in his photogrammetry analysis.
“I don't know. We were matching the photos. So I don't care what the numbers are. I care that the height is the same.”
Welcher explains that his method was photo-height matching rather than reliance on a suspension-setting number; the exchange also leaves the January 29 setting unknown and the source photographs two days later.
“I only have it two days later.”
Acknowledges the suspension height measurement is from two days after the incident, not from the night in question.
“No, the impact didn't register the event. As I pointed out, the trigger — the trigger was from when the accelerator pedal went to 30%... So, the TechStream will never register an event even if you hit a wall at 100 miles an hour — necessarily.”
Critical concession that TechStream data cannot confirm a collision occurred — it only records acceleration/braking events, not impacts.
“Absolutely not. It would have shown up as increased error when we overlaid the point clouds onto the photos— or the point clouds onto the video. If it was an error, it would have showed an error.”
Directly addresses the camera replacement challenge — Welcher explains the methodology has a built-in error check
“So when you look at the failure loads, it depends on what you're doing it with. If I hit you with a 5-lb 2x4 or a 5-lb pillow, they're both 5 lb, but you'd much rather get hit by the pillow than the 2x4.”
Welcher reframes the force calculation challenge by explaining distributed vs concentrated loads, undermining the bone fracture threshold numbers from cross
“No, I don't even know what that is.”
Welcher denies knowledge of Signal, distancing himself from any suggestion of hidden communications with prosecutors
“No. Again, these are direct readings from the vehicle. Again, that speed on this here— you have to correct for the slippage, which I do later on the slide, but that is a direct reading from what the speedometer is seeing.”
Welcher characterizes the displayed reported speed as a direct vehicle reading, while noting that it requires a later slippage correction; the testimony concerns the raw reading rather than whether a collision occurred or the broader analysis.
“So theoretically, my confirmation bias starts with a bias that it didn't happen.”
Welcher's attempt to defend his methodology by invoking a null-hypothesis approach; he later says he did not include everything in the presentation and answers no when asked whether a slide or document presented to the jury expressly showed the no-contact alternative.
“No.”
Welcher concedes he has no slide or document presenting the alternative hypothesis of no contact, despite 130 slides of presentation material
Key Moments
- Before Welcher took the stand before the jury, defense attorney Alessi used a voir dire examination to establish that prosecutor Brennan had initiated last-minute changes to Welcher's PowerPoint presentation during the active trial — a moment that framed the independence of his analysis as a contested issue from the outset.
- Welcher presented Toyota TechStream data showing two triggering events, including a second event with 34 feet of forward travel followed by 53 feet in reverse. The Commonwealth used that event with the physical damage and testing to support its collision theory; Welcher's admitted opinion was that the data and damage were consistent with a collision, not that the event established Read's Lexus struck O'Keefe.
- Using exemplar tail light geometry and pedestrian impact testing, Welcher linked the location and orientation of lacerations on O'Keefe's right forearm directly to the broken tail light assembly of a Lexus LX 570, presenting this as physical corroboration of his collision hypothesis.
- During cross-examination, Alessi revealed that Welcher had performed detailed force calculations for the head injury — arriving at 7,200 pounds — but had performed zero comparable force calculations for the arm injuries, which Welcher argued were the primary mechanism of contact.
- In the final recross, Alessi established that Welcher could not point to a single documented moment where he tested or recorded an alternative hypothesis of no contact between the Lexus and O'Keefe, undercutting his stated null-hypothesis methodology despite his claims of starting from a neutral position.