SAN FRANCISCO (KRON) -- Twelve San Francisco jurors were selected and sworn in on Thursday for the Bob Lee murder trial. They will decide the guilt or innocence of Lee's accused killer, Nima Momeni. The 40-year-old Emeryville man is charged with first-degree murder. Prosecutors said Momeni stabbed the tech mogul in the chest with a knife under the Bay Bridge on April 4, 2023.  Judge Alexandra Gordon will preside over the trial. Gordon told jurors to be prepared for the trial lasting until mid-December. The 12-member jury is comprised of six men and six women. As of Thursday afternoon, attorneys were still hashing out which six people in the remining jury pool will serve as alternates. Nima Momeni walks into the courtroom for his arraignment in San Francisco on May 2, 2023. (Gabrielle Lurie /San Francisco Chronicle via AP, Pool, File) Defense attorney Saam Zangeneh quizzed the prospective alternates by asking, if they had to reach a verdict right now, what would it be? The potential alternates were confused by the question. Zangeneh used the moment to emphasize that every defendant is innocent until proven guilty. Bob Lee’s ex-wife calls Momeni’s sister ‘the whore of high tower’: court documents Prosecutors have a legal burden to prove that Momeni is guilty of first-degree murder at trial, otherwise, he is presumed innocent. Assistant District Attorney Omid Talai is serving as lead trial prosecutor. Zangeneh told the jury pool that the Bob Lee murder case is possibly the biggest case in the country. Judge Gordon snapped at the defense attorney, and emphasized that all cases are "big." Bob Lee Jury selection began on Monday with more than 140 San Francisco residents in the jury pool. Prosecutors, defense attorneys, and Judge Gordon peppered prospective jurors with questions about their personal lives, media exposure to the case, feelings about police, and views on criminal justice. The pool was whittled down one-by-one. One woman said deciding another person's fate was too much to handle. "My anxiety is through the roof. I haven't been sleeping well," she told the judge. Jurors will have to reach a verdict regardless of possible punishment, the judge explained. Gordon said the case is not a death penalty case, and if Momeni is convicted, she will be responsible for deciding Momeni’s sentence. Doors to the courtroom are closed during jury selection on Oct. 7, 2024 in San Francisco. (KRON4 Photo) Momeni's mother attended every day of jury selection this week to support her son. Lee, 43, was a wealthy and successful Bay Area tech executive. He founded the company Cash App, worked for Google as a software engineer, and served as an executive for MobileCoin. Lee is survived by his two daughters, father, and ex-wife.