Commonwealth v. Read — Trial Archive
Person Teri Kun Trial 1UC Davis forensic scientist who testified that DNA testing of swabs from a shirt found no canine DNA and only pig DNA; she said the source was undetermined and that food was one possible source. ← All People
🔬 Expert Witness · UC Davis

Teri Kun

Trial 1
196 lines 5 proceedings
Courtroom still of Teri Kun.

About

Teri Kun is a forensic scientist at UC Davis's veterinary genetics laboratory who specializes in animal DNA analysis. She was called by the prosecution in Trial 1 to report results from testing two swabs taken from a shirt relevant to the case. Her testimony centered on the absence of canine DNA and the presence of pig DNA, whose source she said was undetermined; food was one possible source.

Key Points

  • Kun testified that both swabs from the shirt tested negative for canine DNA using a K9-specific qPCR test, and that the only animal DNA detected was pig. She said the source of the pig DNA was undetermined; food was one possible source, and the species identification test was developed for testing food products.
  • She established that UC Davis's animal DNA laboratory holds the same ANAB accreditation as human DNA crime labs, directly countering any suggestion that animal forensic testing is held to a lower standard than conventional forensic analysis.
  • On cross-examination, Kun testified that she tested only the swabs, not the source garment, and did not know how the agency collected the swabs. She also described the documented chain of custody within the UC Davis laboratory.
  • Jackson's most significant cross-examination point reframed Kun's conclusion: he got her to agree that her negative result did not mean there was no dog DNA on the shirt, only that the swabs she received did not yield a positive result — a distinction that left open the possibility of inhibition, degradation, or inadequate collection.
  • On redirect, Kun countered the inhibition argument by clarifying that the mitochondrial DNA test — which is more sensitive than the nuclear DNA test due to its higher copy number — also returned negative for canine DNA, and that the internal positive control confirmed the test was free of inhibitors.

Trial Record (5)

Trial 1 First Criminal Trial Apr 29, 2024 – Jul 1, 2024 5 proceedings

Day 12

Direct Teri Kun Adam Lally 4 highlights 75 lines spoken
Summary

Forensic scientist Teri Kun testified that two submitted swabs tested positive for pig DNA and negative for canine DNA.

Highlights (4)
Cross Teri Kun Alan Jackson 3 highlights 112 lines spoken
Summary

Kun said her analysis was limited to two swabs and distinguished the inhibited nuclear-DNA test from the meat I.D. test.

Highlights (3)
Quote

“In our meat I.D. test, we also have a test for an inhibitor. It's also called an IPC. It's the same initials. Internal positive control. And that's what did not work in the nuclear testing. It did work and worked very well in the test on the meat I.D. So there wasn't any inhibition that we were seeing on the meat I.D. test.”

Clarifies the differing test results and the absence of inhibition in the meat I.D. test.

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Summary

The court confirmed the defense could proceed during Ms. Little's brief absence before Ryan Nagel was called.