Person Christina Hanley Trial 1Trial 2Christina Hanley is a forensic scientist at the Massachusetts State Police Crime Lab who testified about glass and plastic trace evidence comparisons involving debris from the scene and Karen Read’s vehicle, including comparisons of plastic debris from John O’Keefe’s clothing with sampled tail-light plastic; she said the clothing plastic was consistent in specified properties with the sampled tail-light plastic but could have come from another source with the same characteristics. ← All People
🔬 Expert Witness · MSP Crime Lab

Christina Hanley

Trial 1Trial 2
435 lines 8 proceedings 2 trials
Courtroom still of Christina Hanley.

About

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.

Key Points

  • 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.
  • On cross, Jackson used a chart to isolate item 7-14. Hanley testified that it did not physically match the drinking glass or the item 7-12 pieces; she separately described a bumper piece as consistent with item 7-14 in physical and instrumental properties.
  • 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 testified that the bumper pieces she compared for physical match did not physically match the broken drinking glass.

Trial Record (8)

Trial 1 First Criminal Trial Apr 29, 2024 – Jul 1, 2024 3 proceedings

Day 20

Direct Christina Hanley Adam Lally 5 highlights 88 lines spoken
Summary

Forensic scientist Christina Hanley testified that six recovered glass pieces physically matched a drinking glass and gave qualified comparison results for other glass and plastic debris against taillight material.

Highlights (5)
Quote

“Item 3-2 and the six pieces from 7-12 were at one time together as one unit.”

States the physical-match conclusion for the drinking glass and six recovered pieces.

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Quote

“Accordingly, 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.”

States the qualified association between bumper glass and road glass.

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Quote

“The clear plastic from Item 7-18.18 was found to be consistent in color and instrumental properties with the examined portion of the clear plastic from the taillight.”

States the comparison result for clear plastic recovered from clothing debris and the taillight.

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Show 1 more
Key Moment

Hanley testified that bumper-glass Piece E was consistent in physical and instrumental properties with road glass from Item 7-14, while qualifying that either could share those characteristics with another source.

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Cross Christina Hanley Alan Jackson 3 highlights 52 lines spoken
Summary

Hanley clarified the limits of several glass comparisons, including that Item 7-14 had no physical match with the cup or Item 7-12 pieces; the court deferred admission of a chain-of-custody document.

Highlights (3)
Quote

“So Item 7-12 was previously examined by another analyst in the trace unit. Specifically, "E" and "I" I received when I opened this item for examination, "E" and "I" were taped together because they were found to have a physical match by the analyst who previously examined the item.”

Hanley attributed the earlier E-I physical-match finding to another analyst.

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Quote

“That's correct. So 7-14, there was no physical match between 7-14 and 3-2 or any of the pieces in 7-12.”

Hanley summarized the absence of a physical match between Item 7-14, the cup, and the Item 7-12 pieces.

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Redirect Christina Hanley Adam Lally 2 highlights 6 lines spoken
Summary

Hanley explained the limit on plastic physical-match testing and confirmed a bumper-glass consistency finding; the court sustained a beyond-the-scope objection.

Highlights (2)
Quote

“I didn't examine the plastic pieces for a physical match because there were no other plastic pieces for comparison for a physical match.”

Explains the stated limit of the physical-match analysis for the plastic evidence.

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Trial 2 Retrial Apr 22, 2025 – Jun 18, 2025 5 proceedings

Day 19

Direct Christina Hanley Adam Lally 4 highlights 81 lines spoken
Summary

Christina Hanley testifies about her qualifications and begins describing her glass comparison analysis of evidence from the scene and the defendant's vehicle.

Highlights (4)
Quote

“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.

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Quote

“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.

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Quote

“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.

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Quote

“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.

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Day 20

Direct Christina Hanley Adam Lally 4 highlights 111 lines spoken
Summary

ADA Lally walks Christina Hanley through her glass and plastic evidence comparisons using photographs and instrumental data.

Highlights (4)
Quote

“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.

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Quote

“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.

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Quote

“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.

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Quote

“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.

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Cross Christina Hanley Alan Jackson 4 highlights 86 lines spoken
Summary

Jackson used a demonstrative to organize Hanley's results: two bumper pieces used in physical-match comparison did not physically match the cup, while piece E was microscopically and instrumentally consistent with item 7-14.

Highlights (4)
Quote

“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.

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Quote

“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.

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Quote

“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.

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Quote

“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.

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Redirect Christina Hanley Adam Lally 2 highlights 9 lines spoken
Summary

ADA Lally’s redirect noted that Jackson’s four-category glass chart did not include the plastic items; Hanley said it did not. Cross-examination had addressed the plastic comparison’s nonexclusive result, and Lally’s question restating that comparison was followed by a sustained-as-to-form ruling.

Highlights (2)
Quote

“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

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Recross Christina Hanley Alan Jackson 2 highlights 2 lines spoken
Summary

Alan Jackson's recross elicited Hanley's qualified answer that there was no physical match between the drinking cup and the bumper pieces she compared for physical match; she also said a bumper piece was consistent with item 7-14.

Highlights (2)
Quote

“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.

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