Testimony continued on Thursday in the trial of Nima Momeni and focused on the DNA of the suspected murder weapon.
The key witness on the stand was San Francisco police criminologist Alain Oyafuso, who touched on the finding of a blood sample found on a knife recovered at the scene in April 2023.
"The murder weapon is the centerpiece of this case," said Steven Clark, a legal analyst. "And certainly, the DNA evidence on that weapon is going to be important to solve the mystery of what happened to Bob Lee that night."
The knife was hurdled into the CalTrans years close to where Bob Lee called 911 before being rushed to a hospital, where he died.
In court, it was revealed that Lee's DNA was collected from a blood sample. While Momeni's DNA sample came from two mouth swabs collected by police.
According to Oyafuso's testimony, the DNA swab from the knife handle has the possibility of two contributors. One person contributed 99% of the sample, the other just 1%.
Compared to Momeni's DNA sample, the 99% sample matched by a factor of 1.66 septillions.
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Lee's DNA matched the blade by a factor of 2.89 octillian.
The defense attempted to raise questions about the conclusions, including asking about fingerprints on the knife.
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During prior testimony, an investigator said they did not bother to get fingerprints off the handle to prevent soiling the chances of getting a DNA sample.
The defense also tried to raise questions about the integrity of the swab kits and how DNA is transferred to an object.
"If the jury is persuaded that the DNA was collected and analyzed properly, this goes a long way for the prosecution in proving murder," Clark said.
Testimony is set to resume on Monday, Nov. 4.
