Commonwealth v. Read — Trial ArchiveChristina Hanley
Testimony Impact
Christina Hanley is a forensic scientist with 16 years at the MSP Crime Lab, specializing in trace evidence analysis using microscopy, GRIM refractive index measurement, FTIR spectroscopy, and microspectrophotometry. She was called by the prosecution in both trials to present her findings on glass and plastic debris recovered from the scene, the victim's clothing, and Read's vehicle. Her testimony centered on whether glass fragments from the scene matched the defendant's broken tail light or a drinking glass, and whether plastic debris on the victim's clothing could be linked to Read's vehicle.
Challenges & Responses
What attorneys challenged during examination and how the witness responded.
Jackson challenged Hanley on the precision of her language, pressing her to distinguish between items that were definitively matched versus those that were merely consistent — a difference she acknowledged and maintained throughout. Her methodology and accreditation were not disputed, but the weight of her findings was contested through the framing of what the evidence did and did not connect.
Trial 1 vs Trial 2
In Trial 2, Hanley's testimony was expanded across two days (Days 19–20) compared to a single day in Trial 1, with more detailed walkthrough of photographs and instrumental data under Lally's direct. Jackson's cross in Trial 2 was more structured, deploying a visual comparison chart to systematically walk through which items matched which — a technique that made the gaps in the glass evidence chain more explicit. The recross in Trial 2, which did not occur in Trial 1, further underscored that the only bumper-to-scene glass connection ran through the piece recovered by Trooper Proctor, whose conduct was itself under scrutiny.
Notable Quotes From The Record
“An individual characteristic is when a material can be associated with a single source — for example, a physical match.”
Explains the distinction between class and individual characteristics, contextualizing why some findings are definitive matches and others are consistency findings.
“So item 3-2 and the six pieces from 7-12 were at one time together as one unit.”
Establishes a definitive physical match — the broken drinking glass and scene glass were once a single object.
“the examined portion of the piece of clear glass that I labeled as E from item 3-3 could have originated from the examined portion of the piece of clear glass from item 7-14, or from another source with the same characteristics.”
Links glass from the vehicle's bumper to glass found on the road, though stops short of a definitive match — consistent with but not uniquely identified.
“the red plastic from 7-18.18 could have originated from the red plastic from item 3-1, the tail light, or from another source with the same characteristics.”
Links plastic debris found on the victim's clothing to the defendant's broken tail light, a key piece of the prosecution's theory connecting the vehicle to the victim.
“They were found to be consistent — sorry, they are found to be consistent in physical and instrumental properties.”
Hanley corrects Jackson's use of 'match' to the weaker forensic standard of 'consistent,' a distinction that cuts both ways.
“Correct. That is correct.”
Confirming that the cup was not found to match any items found on the bumper — severing the prosecution's implied glass-to-vehicle link.
“So, 7-14 — there was no physical match between 7-14 and 3-2 or any of the pieces in 7-12.”
Confirms that 7-14 had no physical match to the cup or the other nine scene pieces; Hanley separately described 3-3E as consistent with 7-14 in physical and instrumental properties, not as a unique-source identification.
“Yes, it was six pieces from 7-12. And then it was piece E from item 3-3, from the bumper of the defendant's vehicle, that was found to be — — consistent with clear glass that was found on the ground at 34 Fairview Road, correct.”
Hanley reconfirms both the drinking glass match and the bumper glass consistency finding in a single answer, reinforcing the prosecution's physical evidence connections.
“So the Locard exchange principle — it's kind of the foundation or basis of trace analysis. It is a principle that states that when two objects or two items come into contact with each other there is an exchange of material.”
Establishes the scientific foundation underlying all trace evidence analysis in this case.
“So a physical match is if an item is broken and those pieces are compared to each other and their broken irregular edges fit back together — and they have a jigsaw fit, that would be considered a physical match.”
Defines the physical match standard for the jury before presenting her findings.
“there were, I believe, six pieces of glass from item 7-12 that fit mechanically to the cup that was also recovered from the road, item 3-2.”
In this Day 19 answer, Hanley said she believed six item 7-12 pieces mechanically fit the drinking glass. The approved Day 20 continuation confirmed six and identified them as A, B, C, D, F, and K.
“there was no physical match between those two pieces from the bumper, item 3-3, compared to the glass pieces and the cup that were recovered from the road.”
Hanley reported no physical match for the two item 3-3 bumper pieces used in that comparison. The approved continuation identified them as A and B, said C, D, and E were not used for physical match because of size and condition, and separately reported piece E consistent with item 7-14 in physical and instrumental properties.
“So a physical match is basically — if an item breaks and those items have broken irregular edges, if those pieces come back together like a jigsaw fit, then it's a physical match and they were at one time together as one larger unit.”
Defines the physical match standard for the jury in plain terms.
“So the largest for the red plastic, the largest piece measured — just for visual purposes — it's roughly like the size of a grain of rice. The rest of the pieces were smaller than that.”
Conveys the extremely small scale of the plastic debris recovered from O'Keefe's clothing.
“So the red plastic that I sampled from the debris from the clothing from 7-18.18 was found to be consistent in color, microscopic appearance, and instrumental properties with the portions that I sampled from the red plastic from the tail light.”
Core prosecution finding that red plastic debris from O'Keefe's clothing was consistent in color, microscopic appearance, and instrumental properties with sampled tail-light plastic; Hanley qualified that it could have originated from that sampled plastic or another source with the same characteristics.
“Accordingly, the clear plastic from 7-18.18 could have originated from the clear plastic from item 3-1 or from another source with the same characteristics.”
Standard forensic qualification — consistency does not mean exclusive match, leaving room for defense argument.
“Correct. It could have come from — they could have a common origin, or it could have come from another source with the same characteristics.”
Hanley concedes that the plastic match to the tail light is not conclusive — it could have come from any source with similar properties.
“I did not make any notation that I noted portions that were glass.”
Hanley said she did not make a notation of glass portions, while saying most parts appeared plastic and that she was not certain the entire assembly was plastic.
“I did not note anything that would be maybe consistent with that.”
Hanley, outside her expertise in biological-material examination, said she did not note anything maybe consistent with biological material; this was a bounded visual observation, not a test conclusion.
“Nothing. Um, in a physical match comparison, there was no physical match comparison to the cup.”
Hanley stated that there was no physical-match comparison to the cup; her earlier testimony specified that two of five bumper pieces were used for physical-match comparison.
“I just have the description um that's put in the LIMS system when it's submitted to the lab.”
Establishes Hanley's limited knowledge of evidence provenance — she works from lab submissions, not field recovery details
“No, there was not.”
Confirms the defense chart excluded the clothing-to-tail-light connection from its visual summary
“Correct. To, uh — there was no physical match to the pieces that I compared for physical match from the bumper. Um, there was no physical match to the glass cup, 3-2. 3-2.”
Hanley confines her result to no physical match between the cup and the bumper pieces she compared for physical match.
“It was consistent with item 7-14.”
Hanley confirms the connection but uses the neutral exhibit number rather than adopting Jackson's Proctor framing.
Key Moments
- Hanley's most definitive finding was a physical match between the drinking glass (item 3-2) and six glass pieces recovered from the scene (7-12), establishing that those fragments were once part of the same object.
- Hanley testified that red and clear plastic debris recovered from O'Keefe's clothing was consistent in specified properties with sampled tail-light plastic. She said each could have originated from the comparison material or from another source with the same characteristics, a class-level association rather than a unique source identification.
- During cross-examination in both trials, Jackson used a visual chart to isolate item 7-14 — a single glass piece recovered by Trooper Proctor — as standing alone: it matched neither the drinking cup nor any of the nine other scene glass pieces, undermining the prosecution's implied chain of glass evidence.
- Hanley corrected Jackson's use of the word 'match' for certain comparisons, specifying that the forensic standard for those findings was 'consistent in physical and instrumental properties' rather than a definitive match — a distinction that both sides attempted to leverage.
- Hanley confirmed during cross that no glass found on the vehicle bumper matched the broken drinking glass, a concession that directly challenged the prosecution's theory of how the glass broke during the incident.