The technology consultant charged in the stabbing death of Cash App founder Bob Lee had no motive to kill him and was actually forced to defend himself against Lee, who had become aggressive during a multi-day drug addiction, Nima Momeni's lawyers said in theirs Opening statements on Monday.

Prosecutors say Momeni, 40, planned the attack on April 4, 2023, after an argument over his younger sister Khazar, with whom Lee was friends. They say Momeni took a knife from a unique set in his sister's apartment, drove Lee to a remote area, stabbed him three times and then fled.

“He was stabbed in the heart and left to die,” said Omid Talai, assistant district attorney. “Our victim was stabbed repeatedly, once in the chest, once in the hip and once even in the heart.”

Lee's death at age 43 — after he staggered for help on a deserted street in downtown San Francisco — shocked the tech community, and other executives and engineers paid tribute to the charismatic entrepreneur's generosity and brilliance. When Lee died, he was chief product officer of cryptocurrency platform MobileCoin. He was the father of two children.

Judge Alexandra Gordon has told jurors that the long-awaited trial, which began Monday in San Francisco Superior Court, is expected to last two months. Momeni, who lives in nearby Emeryville, California, has been in custody at a San Francisco hospital since his arrest days after Lee's death.

Momeni pleaded not guilty. If convicted, he faces 26 years to life in prison.

Attorney Saam Zangeneh told jurors that defense attorneys will prove that Momeni bore no ill will toward Lee and that the wound patterns show Momeni was forced to defend himself after Lee pulled a knife out of his pocket, was under the influence of drugs and had slept for a period of only six hours, had consumed cocaine and consumed alcohol for four days.

“We believe that once we present this case … and once we close the gaps, the only valid verdict in this case is an acquittal,” Zangeneh said. “Someone is dead. Nobody likes that, but you have the right to defend yourself.”

Momeni, who has been seen wearing orange prison uniform at previous court hearings, sat with his lawyers on Monday in a dark suit. His mother, who was always present at hearings, was in the courtroom.

Across the courtroom sat members of Lee's family, including his ex-wife, father and brother. Lee's brother put an arm around his father as Lee's 911 call was repeated in court. In it, Lee can be heard repeatedly asking for help without being able to answer the dispatcher's questions about his whereabouts and his name. He said he was stabbed.

Talai, the assistant district attorney, said jurors would hear from a friend of Lee's who was with him and Momeni's sister the day before Lee's stabbing. The friend will testify that Momeni angrily grilled Lee on the phone that night about his sister, drugs and “girls getting naked” and acted like an “overprotective, wannabe tough guy” while Lee was gentle and cheerful, Talai said.

Zangeneh said he would show that the friend was not a reliable witness and that Momeni and Lee exchanged friendly text messages that evening. Lee probably invited Momeni to go to a strip club with him, Zangeneh said.

Surveillance video from Lee's last night shows him entering the posh Millennium Tower downtown, where Momeni's sister lives with her husband, a well-known San Francisco plastic surgeon. The video shows Lee and Momeni leaving the building after 2 a.m. and driving away together in Momeni's car.

Another video will show the two men getting out of the car at a remote spot on the Bay Bridge, and Momeni then stabbing Lee three times, throwing the knife from his sister's kitchen set and quickly driving away, Talai said. Prosecutors will share text messages in which Momeni told his sister the next morning that he did not know what happened to Lee that night but that he had prepared a rape case against him because he thought Lee had attacked Khazar, Talai said .

The lawyer added that a video taken by a San Francisco police officer who chased Momeni before his arrest shows him reenacting the three knife attacks outside his previous lawyer's office, but does not reenact a fight over the knife. which, according to Lee Momeni's lawyers, swung first.

Police recovered a knife with a 10cm blade in the remote area where Lee was stabbed. Prosecutors said tests showed Momeni's DNA on the handle of the gun and Lee's DNA on the bloody blade.

Zangeneh said Monday that police should have examined the handle for fingerprints, namely Lee's. He scoffed at the idea that Momeni essentially brought a “vegetable knife” from his sister's kitchen to kill Lee, saying that Momeni didn't know Lee was injured, let alone mortally wounded.

He said his client was eager to tell his side of the story, but they had not yet decided whether Momeni would testify in his defense.

Family members of Momeni and Lee declined to comment Monday.