Lisa Yelle

Lisa Yelle testified for the Commonwealth on Day 6 about general unknown drug screens she performed on blood and urine in the State Police Crime Lab's Toxicology Unit. She said the screens detected the same substances in both samples but could identify only their presence, not their concentrations. After using Exhibit 183 to refresh her memory, she identified trazodone and quetiapine and confirmed a quetiapine metabolite.

Yelle described a syringe malfunction during testing and said it did not affect the results. She also distinguished her testing work from the reporting analyst's responsibilities, identifying Nicholas Roberts as the reporting analyst. Although she agreed that other laboratories could potentially measure concentrations, she did not know whether samples in this case had been sent elsewhere.

Questions about parent drugs and metabolites developed across her examination. During direct examination, Yelle did not adopt counsel's proposed numerical inference about how many drugs had been consumed. On cross-examination, she agreed that a metabolite is a breakdown product of the same drug and does not necessarily represent another drug consumed. After Reddington stated that the defense stipulated to the blood evidence, chain of custody, and testing, she confirmed that the blood test was good. The Commonwealth asked no further questions, and she was excused.