San Francisco, California (CNN) Jose Ines Garcia Zarate was playing his own "secret version of Russian roulette" when he deliberately fired into an unsuspecting crowd and killed Kate Steinle on a San Francisco Pier two years ago, the prosecution argued before a jury on Monday.

But the defense argued that the 40-caliber Sig Sauer pistol went off accidentally after Garcia Zarate, 45, a Mexican citizen and undocumented immigrant, found it under his seat on the pier. The bullet ricocheted off the ground, traveling about 80 feet before striking Steinle, attorney Matt Gonzalez said.

"But for the ricochet, it does not hit her," Gonzalez told jurors during closing arguments of the roughly month-long trial.

Garcia Zarate has been charged with second-degree murder. Jurors will also be allowed to consider first-degree murder and involuntary manslaughter verdicts.

Jurors will soon have to decide whether Garcia Zarate shot Steinle unintentionally or committed murder in the July 2015 shooting that has drawn national attention -- in part because he had been deported from the United States five times.

Prosecution: 'The gun gave him power'

Lead prosecutor Diana Garcia told jurors Garcia Zarate had time to think about his actions as he sat in a chair on San Francisco's Pier 14 for 23 minutes that day on July 2015. He was "staring at people and laughing" looking to see who he would shoot, the prosecutor said.

Garcia Zarate then pulled out the concealed .40-caliber Sig Sauer and "pointed it at people and pulled the trigger" before ditching the weapon and fleeing the area, she said.

"Kate Steinle was wiped off the earth" because of the defendant, the prosecutor said, adding "the gun gave him power."

"It was his secret. He wanted to fire the gun," Garcia said.

In a police interrogation, Garcia Zarate admitted to firing the gun, but also claimed he was aiming at a seal.

"If it was an accident, why didn't he say so?" Garcia asked.

The shooting could not have been accidental as the defense has argued, the prosecutor said, because it takes force to pull the trigger.

"It did not just go off," she said.

Prosecutors have argued Garcia Zarate immediately tried to cover his tracks by throwing his gun into the San Francisco Bay, then fleeing the scene.

Prosecutor Diana Garcia addresses jurors in the murder trial of Jose Ines Garcia Zarate.

Defense: Client 'had no motive'

The defense contends Garcia Zarate's rushing away from the scene can be chalked up to nervousness.

Garcia Zarate found the gun wrapped in a T-shirt or cloth under his seat on the pier seconds before it accidentally went off, according to the defense. Authorities said the gun had been stolen from an off-duty Bureau of Land Management agent's car four days earlier.

The defense has argued that the Sig Sauer is prone to accidental discharges, and called its own forensic firearms expert who testified that the facts of the shooting point to an accidental discharge.

Gonzalez told jurors it doesn't take much effort to pull the trigger of the Sig Sauer, comparing it to the trigger of a squirt gun.

Defense attorney Matt Gonzalez makes closing arguments in the murder trial of Jose Ines Garcia Zarate.

He argued that video evidence shows his client bending down before the gun goes off, meaning he found the weapon moments before.

"Nothing peculiar about a homeless person who decides to pick something up and look at it," Gonzalez said.

The prosecution witness who said she saw Garcia staring and laughing before the shooting never told police he was laughing, Gonzalez told jurors.

Gonzalez said his client "had no motive; he didn't know Ms. Steinle."

The attorney suggested that some of his client's conflicting answers to police were from a lack of sleep.

Garcia Zarate told detectives in "two, three, four different ways that he found the gun on the pier," Gonzalez said.

"This case should not have been charged. But if it was going to be charged, it should have been charged as manslaughter," Gonzalez said.

The defense attorney asked the jury: "Is it manslaughter or is it an accident?"



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Steinle's death stirred an already heated debate over immigration.

Before the shooting, officials in San Francisco, a so-called sanctuary city, had released Garcia Zarate from custody instead of turning him over to immigration authorities. Freya Horne, chief legal counsel to the San Francisco County Sheriff, said in a 2015 interview that he was let go because there was no legal cause to detain the suspect.

Steinle's family filed a lawsuit in 2016 alleging that San Francisco and its former sheriff were partly to blame for Steinle's death, because officials never notified Immigration and Customs Enforcement when Garcia Zarate was released from a local jail in April 2015. City officials have said they're not liable for a former inmate's actions. A federal judge dismissed the family's claims against San Francisco and former Sheriff Ross Mirkarimi earlier this year.

The case also has become a rallying cry for President Donald Trump and GOP politicians, who have invoked Steinle's name in decrying sanctuary cities and promoting the construction of a border wall.

In June, the House of Representatives passed " Kate's law ," a measure named for the victim that would increase maximum prison penalties for immigrants caught repeatedly entering the United States illegally. But it's unlikely to have enough votes to pass the Senate, which struggled with Kate's Law last year.

'Dad, help me'

Steinle took a stroll with her father and a friend on the evening of July 1, 2015, when the bullet struck her in the back and ruptured a major artery. Steinle's last words were "Dad, help me. Help me," according to the prosecutor.

Steinle's family has been present for part of the trial. James Steinle testified about the "loud" solo shot that rang out on the pier that killed his daughter.

"I couldn't figure out what happened," he said to the jury.

"I gave her mouth to mouth. And waited for the paramedics to show up and asked people to call 911."

Kate Steinle died a short time later at the hospital.

Garcia Zarate was arrested a short distance from the scene after a police officer noticed he matched the description of the suspect.

Garcia Zarate was formerly known as Juan Francisco Lopez-Sanchez, one of several aliases he is known to have used. CNN and other media outlets previously identified him as Juan Francisco Lopez-Sanchez.

Questions about integrity of translation

A court sketch of Jose Garcia Zarate, an undocumented Mexican immigrant on trial for the murder of Kate Steinle.

One of the key pieces of evidence included a recorded police interview with a Spanish translator present. Garcia Zarate gave conflicting statements but eventually acknowledged firing the shot.

"What were you aiming at?" the detective asked.

"A sea lion," Garcia answers in Spanish.

But the tape reveals that he also told police that he stepped on the gun, causing it to fire. "I grabbed it and tossed it," he said referring to the weapon being thrown into the water.

Prosecutors argued his assertion is not credible.

But the defense says the interview is problematic due to translation errors.

In a printed translation of the interview, a police detective asked, "Did you pull the trigger?" Garcia Zarate answered, "Yes."

But according to the defense, the word "trigger" (or "gatillo" in Spanish) was never used. Instead, they say Garcia Zarate was asked, "Did you fire?" Gonzales contends it's an important distinction since he argues Garcia Zarate didn't intentionally pull the trigger.

"The people's entire theory of the case from the beginning has been he pulled the trigger, it takes a human finger," Gonzales told reporters.

If jurors were to believe that Garcia Zarate never confessed to actually pulling the trigger, the defense hopes they may be more inclined to decide the shooting was an accident, acquitting him of murder.

The defense will wrap up closing arguments on Tuesday.

CORRECTION: This story has been updated to correct the spelling of Kate Steinle's name in the headline.