Commonwealth v. Read — Trial Archive
Trial 2 Trial Day
◀ Day 30 Trial 2 Day 32 ▶

Day 31 - June 11, 2025

Judge Beverly J. Cannone · Trial 2 · 5 proceedings · 1,845 utterances

Day 31 of 36
Appearing:
🏛️ Hank Brennan 🛡️ Alan Jackson 🔬 Andrew Rentschler

Defense biomechanical expert Dr. Andrew Rentschler completes testimony under aggressive cross-examination, and the defense formally rests its case.

Full day summary

Dr. Andrew Rentschler concluded his direct examination presenting impact testing results and slow-motion video analysis concluding O'Keefe's injuries are inconsistent with a Lexus tail light strike. ADA Hank Brennan conducted an extensive and damaging cross-examination, attacking Rentschler's credibility through a sequestration violation before Trial 1, deleted text messages with the defense, and a publication record confined entirely to wheelchair research with nothing on pedestrian collisions. Brennan also confronted Rentschler with physical evidence he had excluded from his analysis — tail light fragments in O'Keefe's clothing, glass found in his nose, and scene debris — and pressed him on how the tail light broke if not from striking O'Keefe. Alan Jackson rehabilitated Rentschler on redirect, eliciting his ultimate opinion to a reasonable degree of scientific certainty that none of O'Keefe's injuries were consistent with being struck by the Lexus. After the jury was dismissed, the defense formally rested, David Yannetti renewed the motion for required finding, and Judge Cannone scheduled a charge conference for Thursday with closing arguments set for Friday.

Key Moments
  • Rentschler testified that 36 arm abrasions, absent hand fractures, and absent lower-extremity injuries are collectively inconsistent with an SUV strike at any tested speed.
  • Brennan impeached Rentschler with his own prior sworn testimony admitting that receiving trial updates from his client before Trial 1 'certainly helped prepare me to understand what was going on during the trial,' directly contradicting denials made earlier in the cross.
  • Brennan established that none of Rentschler's peer-reviewed publications address pedestrian collisions and that his three cited references do not endorse using crash test dummies for superficial skin injury analysis.
  • Rentschler could not explain how the tail light broke if not from contact with O'Keefe, leaving an unresolved gap in the defense narrative as his final impression on the jury.
  • The defense formally rested its case, with Yannetti renewing the motion for required finding; Judge Cannone set a charge conference for Thursday and closing arguments for Friday.
Notable Quotes
Andrew Rentschler
“I said it certainly helped prepare me to understand what was going on during the trial. Yes.”
The day's most damaging impeachment moment: Brennan forced Rentschler to read his own prior sworn admission that receiving trial information helped him prepare, directly contradicting denials made minutes earlier and raising the sequestration violation as a credibility issue.
Andrew Rentschler
“No, they are not.”
Rentschler's closing statement of his ultimate defense opinion — delivered to a reasonable degree of scientific certainty — framing the entire day's testimony in a single word.
Andrew Rentschler
“Oh, I — I don't know. There's no evidence of how it broke.”
Brennan's final substantive exchange with Rentschler left the jury with an unanswered question: if the tail light did not break by striking O'Keefe, Rentschler had no explanation for how it broke at all.

Andrew Rentschler - Direct (Part 2)

Dr. Rentschler presented biomechanical testing results challenging whether John O'Keefe's arm injuries and body placement are consistent with being struck by Karen Read's Lexus SUV.

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Direct
Andrew Rentschler Alan Jackson
700 utt.

Dr. Andrew Rentschler continued his direct examination by Alan Jackson, presenting a PowerPoint-based analysis critiquing Aperture's paint transfer test and offering ARCCA's own impact testing results. Rentschler testified that O'Keefe's 36 superficial abrasions were inconsistent with tail light contact, noting the abrasion directionality did not match expected kinematics, the sweatshirt had only 9 holes versus 36 abrasions, and X-rays showed no fractures despite forces at 24 mph exceeding bone fracture thresholds. He demonstrated through slow-motion video analysis that Aperture's surrogate appeared to lean into the vehicle during the paint transfer test rather than passively receiving contact. Rentschler concluded that an arm-only strike could not propel a body 7-10 feet perpendicular to the vehicle's travel, and that the absence of lower extremity injuries, hand fractures, bruising, or center-of-mass damage was inconsistent with being struck by an SUV at speed.

Andrew Rentschler - Cross

ADA Hank Brennan cross-examines defense biomechanical expert Dr. Andrew Rentschler, challenging his independence, methodology, credentials, and failure to account for physical evidence found at the scene.

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Cross
Andrew Rentschler Hank Brennan
990 utt.

ADA Hank Brennan conducted an extensive cross-examination of Dr. Andrew Rentschler, attacking multiple dimensions of his testimony. Brennan established that Rentschler received trial updates from his employer before testifying in Trial 1 despite a sequestration order, socialized with the defense team after testifying, and deleted text messages with the defense. Brennan challenged Rentschler's peer-reviewed publications as exclusively wheelchair-related with nothing on pedestrian collisions, and demonstrated that the three citations supporting his arm-injury opinion did not endorse using crash test dummies for skin injury analysis. Brennan confronted Rentschler with physical evidence he had not considered — tail light shards in O'Keefe's clothing, his shoe near the curb, his hat in the yard, glass from his nose, and a broken drinking glass — pressing repeatedly on why a reconstruction expert would exclude scene evidence. Brennan closed by impeaching Rentschler with his own prior sworn testimony admitting that receiving trial information from his employer 'certainly helped prepare me to understand what was going on during the trial,' contradicting his denials earlier in the cross.

Andrew Rentschler - Redirect/Recross

Defense redirect and prosecution recross of Dr. Andrew Rentschler, a collision physics expert, on injury patterns and evidence from the Fairview scene.

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Redirect
Andrew Rentschler Alan Jackson
72 utt.

Alan Jackson conducted a focused redirect examination of Dr. Andrew Rentschler, addressing key points raised during ADA Brennan's cross-examination. Jackson clarified that the entity providing Rentschler trial information before Trial 1 was a client (not his employer ARCCA), and that the information did not affect his opinions. Jackson then walked Rentschler through the fender vault collision distinction, the physics of debris trajectory (explaining why glass in O'Keefe's nose was inconsistent with a tail light strike from behind), and the chain-of-custody questions surrounding plastic pieces found at 34 Fairview. Rentschler testified that none of the plastic was found during the initial search when O'Keefe's body was discovered. Jackson concluded by eliciting Rentschler's ultimate opinion — held to a reasonable degree of scientific certainty — that none of O'Keefe's injuries were consistent with being struck by the Lexus. ADA Brennan briefly recrossed, asking whether O'Keefe could have been clipped rather than struck; Rentschler said the evidence did not support that scenario either.

Recross
Andrew Rentschler Hank Brennan
34 utt.

ADA Hank Brennan conducted a short recross of Dr. Andrew Rentschler, pressing on the timing and chain of custody of evidence found at 34 Fairview Road. Brennan established that Rentschler did not know the limits of the Canton Police Department's initial search area around O'Keefe's body, could not recall whether tail light pieces were found in that same area or elsewhere on the lot, and did not know how the tail light broke. Brennan challenged Rentschler's repeated invocation of 'the physics' by pressing whether common sense and the totality of evidence should factor into analysis. The exchange ended with Brennan referencing a documentary in which Rentschler appeared to celebrate one of his trial answers, drawing a sustained objection from the defense before Brennan closed with the unanswered question of how the tail light broke.

Procedural - Motions

End-of-day motions session covering disputes over Dr. Rentschler's PowerPoint admission, exhibit numbering for sweatshirt evidence, defense resting its case, and scheduling closings for Friday.

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Procedural
Procedural - Motions
49 utt.

After the jury was dismissed, Judge Cannone addressed several pending matters. The defense objected to admitting Dr. Rentschler's PowerPoint presentation as substantive evidence, arguing it was a strategic decision not to object earlier and that the same standard applied to other experts' materials. Jackson argued the PowerPoint should be admitted since specific slides were already removed at the prosecution's request. The judge deferred ruling, asking Jackson to identify which video slides were not already in evidence. Brennan announced the defense would not call further witnesses, effectively resting. Yannetti moved to renew the motion for required finding on all evidence, deferred to the next morning. The court resolved exhibit numbering for sweatshirt-related documents (marked as 230 A through D), scheduled a charge conference for 10:00 AM the following day without jurors, and set closing arguments for Friday morning with discussion of time limits.

◀ Day 30 Trial 2 Day 32 ▶