Tess Chart Testimony & Transcripts - Commonwealth v. Read

About

Tess Chart analyzed a hair recovered from a vehicle’s exterior rear panel after another analyst reported that the sample did not yield a usable STR profile. She testified that its mitochondrial DNA profile was consistent with John O’Keefe’s reference profile, so he could not be excluded as a possible contributor. Chart said the profile was not found in the listed EMPOP databases and that the comparison supported excluding at least 99.895 percent of the population at a 95 percent confidence interval. The defense declined to cross-examine her.

Trial Record (1)

Trial 1 First Criminal Trial Apr 29, 2024 – Jul 1, 2024 1 proceeding

Day 24 June 13, 2024

Direct Tess Chart - Direct Examination Tess Chart Adam Lally 3 highlights 65 lines spoken

Summary

Forensic DNA analyst Tess Chart testified that hair sample EO1 was consistent with John O'Keefe's mitochondrial DNA profile and supported an exclusion of at least 99.895 percent of the population.

Highlights (3)

Quote

“So the mitochondrial profile that was obtained from the sample, the hair sample, was consistent with the mitochondrial DNA profile obtained from John O'Keefe. So, therefore, John O'Keefe cannot be excluded as a possible contributor of that hair.”

Chart stated her comparison conclusion for the hair sample and O'Keefe's reference profile.

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Quote

“Sure. So by not seeing it in the database, this means that we are able to exclude at least 99.895 percent of the population from being a source of that evidence.”

Chart gave the statistical exclusion she associated with the database comparison.

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Key Moment

Chart explained her qualifications, Bode Technology's laboratory standards, and her mitochondrial-DNA training before offering opinions.

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