Nieto. Mr. Nieto became further—what’s the right word?—distressed, moving very quickly and rapidly left to right, trying to keep his chips away from Luna. He ran down to these benches and jumped up on the benches, my dog following. She was at that point vocalizing, barking, or kind of howling.” The dog had Nieto cornered on the bench while its inattentive owner was forty feet away—in his deposition for the case, under oath, his exact words were that he was distracted by a female “jogger’s butt.” Snow said, “I can imagine that somebody would—could assume the dog was being aggressive at that point.” The dog did not come when he called, but kept barking.

Nieto, Snow says, then pulled back his jacket and took his Taser out, briefly pointing at the distant dog owner before he pointed it at the dog baying at his feet. The two men yelled at each other, and Snow apparently used a racial slur, but would not later give the precise word. As he left the park, he texted a friend about the incident. His text, according to his testimony, said, “in another state, like Florida, I would have been justified in shooting Mr. Nieto that night”—a reference to that state’s infamous “stand your ground” law, which removes the obligation to retreat before using force in self-defense. In other words, he apparently wished he could have done what George Zimmerman did to Trayvon Martin: execute him without consequences.

Soon after, a couple out walking their dogs passed by Nieto. Tim Isgitt, a recent arrival in the area, is the communications director of a nonprofit organization founded by tech billionaires. He now lives in suburban Marin County, as does his husband, Justin Fritz, a self-described “e-mail marketing manager” who had lived in San Francisco about a year. In a picture one of them posted on social media, they are chestnut-haired, clean-cut white men posing with their dogs, a springer spaniel and an old bulldog. They were walking those dogs when they passed Nieto at a distance.

Fritz did not notice anything unusual but Isgitt saw Nieto moving “nervously” and putting his hand on the Taser in its holster. Snow was gone, so Isgitt had no idea that Nieto had just had an ugly altercation and had reason to be disturbed. Isgitt began telling people he encountered to avoid the area. (One witness who did see Nieto shortly after Isgitt and Fritz, longtime Bernal Heights resident Robin Bullard, who was walking his own dog in the park, testified that there was nothing alarming about him. “He was just sitting there,” Bullard said.)

At the trial, Fritz testified that he had not seen anything alarming about Nieto. He said that he called 911 because Isgitt urged him to. At about 7:11 p.m. he began talking to the 911 dispatcher, telling her that there was a man with a black handgun. What race, asked the dispatcher, “Black, Hispanic?” “Hispanic,” replied Fritz. Later, the dispatcher asked him if the man in question was doing “anything violent,” and Fritz answered, “Just pacing, it looks like he might be eating chips or sunflowers, but he’s resting a hand kind of on the gun.” Alex Nieto had about five more minutes to live.

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San Francisco, like all cities, has been a place where when newcomers arrive in a trickle, they integrate and contribute to the ongoing transformation of a place that is not static in demographics and industries. When they arrive in a flood, as they have during economic booms since the nineteenth-century gold rush, including the dot-com surge of the late 1990s and the current tech tsunami, they scour out what was there before. By 2012 the incursion of tech workers had gone from steady stream to deluge, and more and more people and institutions—bookstores, churches, social services, nonprofits of all kinds, gay and lesbian bars, small businesses with deep roots in the neighborhoods—began to be evicted. So did seniors, including many in their nineties, schoolteachers, working-class families, the disabled, and pretty much anyone who was a tenant whose home could be milked for more money.

San Francisco had been a place where some people came out of idealism or stayed to realize an ideal: to work for social justice or teach the disabled, to write poetry or practice alternative medicine—to be part of something larger than themselves that was not a corporation, to live for something more than money. That was becoming less and less possible as rent and sale prices for homes spiraled upward. What the old-timers were afraid of losing, many of the newcomers seemed unable to recognize. The tech culture seemed in small and large ways to be a culture of disconnection and withdrawal.

And it was very white, male, and young, which is why I started to call my hometown “Fratistan.” As of 2014, Google’s Silicon Valley employees, for example, were 2 percent black, 3 percent Latino, and 70 percent male. The Google bus—the private luxury shuttles—made it convenient for these employees who worked in the South Bay to live in San Francisco, as did shuttles for Facebook, Apple, Yahoo!, and other big corporations.