UPDATE: Gun in Kate Steinle killing designed to prevent accidental discharges, expert testifies

The gun that killed Kate Steinle will not fire unless the trigger is pulled, a firearms expert testified Tuesday in a murder trial that hinges on whether the shooting was an accident.

Gerald Andrew Smith, a supervising criminalist with the San Francisco police crime lab, tested the stolen law enforcement handgun that Jose Ines Garcia Zarate is accused of firing at Steinle on Pier 14 in July 2015.

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Garcia Zarate is an undocumented homeless man, but his legal status is not at issue in the trial despite President Donald Trump using the killing to call for an immigration crackdown during his presidential campaign.

Prosecutor Diana Garcia called Smith to the stand as a firearms expert during the sixth day of the trial since opening statements.

The alleged murder weapon is a .40 caliber Sig Sauer P239 that was stolen from a Bureau of Land Management ranger who left the handgun unsecured in his car when he parked in San Francisco just days before the shooting.

Smith said both law enforcement and military issue the weapon.

“It is a well-made gun,” Smith said. “It has a good reputation of quality.”

The handgun has internal safety mechanisms that prevent it from discharging unless the trigger is pulled, according to Smith. The mechanisms are designed to prevent an accidental discharge when a gun is dropped or mishandled.

“If this gun was dropped, the only way for it to discharge is if something pulled the trigger during the dropping of the gun,” Smith said.

But Defense attorney Matt Gonzalez said that the gun could have discharged on accident when Garcia Zarate found it on the pier wrapped up in something like clothing.

The prosecutor needs to prove intent for the jury to convict Garcia Zarate on second-degree murder.

“I’m not saying that it’s impossible that his finger caused it,” Gonzalez told reporters outside the courtroom. “But it’s also possible that in the movement of whatever this was wrapped in, the fabric was also in there and being pulled back.”

The gun fires in two modes, one of which requires less force to pull the trigger and discharge the weapon than the other.

Smith said the gun fires in single-action mode with between 4.8 and 5.5 pounds of pressure applied to the trigger, while double-action mode requires between 9 and 9.8 pounds of pressure to fire.

But during cross-examination from Gonzalez, Smith said a gun could discharge with less pressure applied to the trigger than a standard trigger pull.

For instance, a gun with a standard trigger pull of 4.4 pounds could discharge under just 3 or 3.4 pounds of pressure if applied at the tip or another part of the trigger than usual.

“If this gun were wrapped in something, most likely Mr. Garcia Zarate’s hands and fingers would have been probing the object as he handled it,” Gonzalez said. “That’s when he could have hit the side of a trigger and depressed it back.”

But Smith said the gun does not have a hair trigger that is easily pulled with under 2 pounds of pressure.

“We want the judge to allow the jury to dry fire it in single-action mode,” Gonzalez said. “I am very confident that if you handle this firearm in single-action mode and depress the trigger, it’s very light.”

It requires 2.9 pounds of pressure on average to push a key on a computer, according to Gonzalez.

Smith said he does not know whether the bullet that struck Steinle was fired in single- or double-action mode, but Gonzalez said the gun could have discharged in single-action mode when Steinle was shot.

The handgun is in single-action mode when the hammer is cocked. After the first shot, the gun will continue to fire in double-action mode unless the shooter manually switches the weapon back to single-action mode.

Jurors viewed the gun in court on Tuesday when a sheriff’s deputy walked the weapon around the courtroom. Smith also displayed the weapon and at one point held up the bullet that the medical examiner pulled from Steinle’s body.

The bullet ricocheted off Pier 14 before it hit her in the back, which Gonzalez has used to argue that the shooting was accidental.

Smith said the bullet had heavy gouges on one side that “look very typical of a ricochet.”

Smith matched the flattened bullet to the stolen Sig Sauer. Divers recovered the weapon from the San Francisco Bay a day after Garcia Zarate allegedly shot Steinle and threw the gun off the pier.

Divers placed the weapon in a Pelican Case filled with murky water from the Bay on July 2, 2015.

Smith said he kept the gun submerged in Bay waters until he tested it July 9, except for when he removed the weapon to test it for DNA on July 6.

Editor’s note: This story has been updated to include additional information.


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