SanFrancisco – San Francisco police criminalist Alain Oyafuso took center stage Thursday in the Nima Momeni murder case.

Oyafuso, an expert in DNA analysis, stated that Momeni’s DNA was found on the handle of a Joseph Joseph brand knife and that the blood on the knife belonged to the victim, Cash App founder Bob Lee.

The prosecution says the defendant threw the knife over the fence after stabbing Lee in April 2023. Authorities say a second Joseph Joseph knife was found in the kitchen of Momeni’s sister’s apartment.

But the defense says it was Lee who acted aggressively and came at Momeni with a knife during a drug-fueled bender, and that Momeni then took the knife and stabbed Lee in self-defense.

If that’s the case, KTVU legal analyst Michael Cardoza says it wouldn’t be a surprise if both men’s DNA was found on the knife.

“So the defense has to be extremely careful not to bore the jury and not to lose confidence in them. Now the important question is who brought the knife,” Cardoza said. “But to me DNA has nothing to do with it.

Saam Zangeneh, one of Momeni’s five lawyers, says the defense does not dispute that Momeni touched the knife. However, he said the DNA expert stated that a small percentage of the DNA on the handle belonged to someone else.

“If this was a detective story, my client would be in trouble. It’s not,” Zangeneh said. “So I think that’s one of their strongest pieces of evidence, or at least what they think is one of their strongest pieces of evidence, which I think has largely faded away.”

The hearing will continue on Monday.

Henry Lee is a KTVU crime reporter. Email Henry at [email protected] and follow him on Twitter @henrykleeKTVU and www.facebook.com/henrykleefan