See Mission Local’s full coverage of the Alex Nieto shooting here.

A man who was at Bernal Heights Park the day Alex Nieto was shot and killed testified Tuesday that Nieto pointed a taser at him about 30 minutes before four San Francisco police officers say they mistook that taser for a pistol.

The officers fatally shot Nieto in the confrontation that ensued, and are now facing a federal civil suit from his parents for wrongful death and civil rights violations stemming from the March 21, 2014, incident.

Evan Snow, a witness called by the city, testified on Tuesday that he was walking his one-year-old Siberian husky at Bernal Heights Park that day when he came across Nieto eating chips near a park bench.

Snow said he noticed Nieto’s “tense demeanor and tight shoulders” and was worried that his dog would go for Nieto’s food. He had already called for his dog get away from Nieto once when the dog sprinted towards Nieto from 40 feet away and began barking at him, prompting Nieto to jump on a bench.

“He [then] reached [for his waistband] and he grabbed the item in the holster, he removed it from the holster, and he pointed it directly at me,” Snow testified.

Nieto then pointed the object at Snow’s dog, he said, at which point Snow realized it was a taser, called his dog away, and hurried out of the park. Snow added that Nieto swore at him while he was leaving the park.

Asked what he thought when Nieto drew the taser, Snow said he was scared for his life. “I’m gonna get shot, I’m gonna die here right now,” he recalled thinking.

Lateef Gray, an attorney for the Nieto family, tried to cast doubt on Snow’s character by pointing out that he used a racial slur for Nieto after the incident and sent joking text messages to a friend. In those messages, Snow wrote that he wished he were in Florida so he could have shot Nieto, a reference to that state’s stand-your-ground law, Gray said.

Snow said Tuesday he “may have” sent those messages but did so because he was “traumatized by the incident.”

Grey also pointed out that Snow had testified in an earlier deposition that a female runner’s behind distracted him in the critical moment when his dog sprinted towards Nieto.

“You were staring at her butt, correct?” asked Lateef Gray, one of the attorneys for Nieto’s parents.

Snow said “her back was to me and I believe I used that term” but denied later in his testimony that he was distracted specifically by her behind.

Gray read from a deposition from September in which Snow said the runner’s rear was “one of the three things [he] remembered about the incident,” which Snow dismissed Tuesday as a means of “trying to add a little humor to the situation.”

Gray said September’s deposition also indicated Snow was prejudiced against Nieto because of Nieto’s clothing. Nieto was dressed in black jeans, a red 49ers jacket, and a 49ers ballcap.

In that deposition, Snow said that he made a quick judgment to avoid Nieto based upon his “experience at Berkeley High” with “gang members.”

During Tuesday’s testimony, however, Snow denied that he stereotyped Nieto.

“No, that is absolutely incorrect,” Snow said. “I think in previous [testimony] I said he was dressed as if he were in a gang, but I did not assume [that he was].”

Snow is the only non-police witness to testify that Nieto pointed a taser that day. His encounter — and the 911 call to report Nieto — have been the subject of intense scrutiny from advocates for Nieto, many of whom have said that Nieto only drew such attention because his appearance may have been frightening to outsiders.

Advocates have linked the shooting death of Nieto to the effects of gentrification on the Mission District, claiming that newcomers unfamiliar with local culture are quick to call the police on neighbors they mistake for criminals or gang members.

The 911 caller in Nieto’s shooting had lived in San Francisco for about a year at the time of the shooting, while Snow did not say how long he had lived in the city at that time.

Also testifying Tuesday was Don Cameron, a former Berkeley police officer and frequent expert witness for police departments. Cameron testified that police actions in their encounter with Nieto were justified given the immediate threat officers believed he posed.

His testimony was meant to counterbalance testimony given Monday by Roger Clark, a retired Los Angeles police officer frequently called to testify by the firm representing Nieto’s parents. Clark said that officers were too hasty to approach Nieto in a public park and should have crafted a plan beforehand.

Closing arguments are scheduled to begin at 9 a.m. on Wednesday. The eight-person jury will begin deliberations after that and decide whether to award Nieto’s parents financial damages and, if so, how much. That deliberation could take hours or days.