On the 34th floor of the building, 55-year old failed entrepreneur Gian Luigi Ferri stepped out of the elevator and opened fire with two tech nine handguns fitted with hellfire triggers.
"When Ferri got off the elevator and started spraying bullets the first people that were killed were Jack and Jody," said wife of one of the victims Carol Kingsley.
Kingsley's husband, Jack Berman and his client Jody Sposato were in the conference room next to the elevator on the 34 floor. But it wasn't Berman's law firm. He was scheduled to be on a flight to Los Angeles that afternoon.
"You can see the bullet holes going through the airline ticket that were in the pocket of his jacket," said Kingsley.
Twenty years later, Kingsley still didn't know that it was her friend Chuck Ehrlich, an attorney at Pettit and Martin, which reserved the conference room that afternoon.
"It just happened that the deposition that was going on there went on for an extra day; beyond what they expected," said Ehrlich.
Kingsley says it must have meant that Ehrlich was meant to live.
"And he was meant to take on this as part of his life it sounds like," she said.
What Ehrlich took on, along with Kingsley and a group of San Francisco lawyers, was what has become the Law Center to Prevent Gun Violence.
"I don't remember it very well, but I'm told by people that I said something like, 'we just can't not do something,'" said Ehrlich.
"They were going to marshal their expertise and do what lawyers do so well and that is, write legislation, be involved in creating laws that would address the problem," said Kingsley.
In the last 20 years, the center's efforts have resulted in 30 state and local laws. And gun deaths have decreased in California by 56 percent.
Friday night, Kingsley will be honored at the center's annual dinner for her work to prevent gun violence.
"I couldn't walk away from a problem and not be part of working for a solution," she said.
The 101 California shooting happened twenty years ago this Monday.