Expert says 99% of DNA found on handle of knife that killed Bob Lee belongs to Nima Momeni
Thursday's proceedings in the Bob Lee murder trial turned to the knife used to kill the Cash App founder and what the DNA evidence revealed.
Most of the day's testimony featured questioning of forensic DNA expert Alain Oyafuso regarding DNA found on the Joseph Joseph brand paring knife blade and handle.
Defendant Nima Momeni is accused of fatally stabbing Lee in April of last year in San Francisco's Rincon Hill/East Cut neighborhood. The trial resumed on Wednesday with the presentation of video evidence to the jury, including grainy footage that allegedly showed the moment Momeni critically injured Lee.
The defense has maintained their client acted in self-defense when they say Lee attacked Momeni in a "drug-fueled rage" after a multi-day bender. But Thursday's testimony by Oyafuso could sow doubt in their theory.
Oyafuso explained that 98% of the DNA on the blade of the murder weapon belonged to Lee, while 99% of the DNA on the handle of the weapon was Momeni's. However, Momeni's attorney Saam Zangeneh said the testimony doesn't change their argument that Momeni acted in self-defense.
"I don't think this affects it at all guys," he told CBS News Bay Area. "The video shows Nima was the last one holding the knife. We're not disputing that."
The prosecution hopes the data will speak for itself. Oyafuso explained that all parts of the murder weapon were tested for both men's DNA. They found "limited support" for Momeni's DNA on the blade or for Lee's DNA on the handle.
The expert said the likelihood of Lee's DNA being on the blade is 1,660,000,000,000,000,000,000,000 or 1.66 septillion times greater than that of a random, unrelated person. They also said the likelihood of Momeni's DNA being on the handle of the knife is 2,980,000,000,000,000,000,000,000,000 or 2.98 octillion times greater than that of a random, unrelated person.
Attorney Shannan Dugan, who sat in on Thursday's proceedings, said that may not be enough to convince the jury that only Momeni handled the knife.
"If you were handling that knife a lot before in an explainable way, the defense could argue that's why his DNA was on the knife. This witness said on the stand, he could not determine the time of the transfer, motive or whether it was a direct or indirect transfer," Dugan said.
The trial resumes Monday with questioning by witnesses called by prosecutors.