Phil Van Stockum is a mechanical engineer who lives in San Francisco and occasionally writes at abinitioblog.com. He is not a lawyer.

I was an alternate juror in the Kate Steinle murder trial in San Francisco. I didn’t get a vote, but I saw all of the evidence and the jury instructions, and I discussed the verdict with the jury after it was delivered. Most of the public reaction I've seen has been surprise, confusion and derision. If these were among your reactions as well, I'm writing to explain to you why the jury was right to make the decision that it did.

I’m not a lawyer, but I understood the law that was read to us in this case. Defendants in this country have the right to a presumption of innocence, which means that if there is a reasonable interpretation of the evidence that favors a defendant, the jury must accept that interpretation over any others that incriminate him. This principle is a pillar of the American justice system, and it was a significant part of our jury instructions.


Jose Ines Garcia Zarate, the undocumented immigrant who was accused of killing Steinle, was charged with first degree murder and the lesser included offenses of second degree murder and involuntary manslaughter. When the prosecution rested its case, it seemed clear to me that the evidence didn’t support the requirements of premeditation or malice aforethought (intentional recklessness or killing) for the murder charges. After having heard the evidence, I agreed with the defense’s opinion that the murder charges should not have been brought. The evidence didn't show that Garcia Zarate intended to kill anyone.

These are some of the facts that were laid out to us: Zarate had no motive and no recorded history of violence. The shot he fired from his chair hit the ground 12 feet in front of him before ricocheting a further 78 feet to hit Steinle. The damage to the bullet indicated a glancing impact during the ricochet, so it seems to have been shot from a low height. The gun, a Sig Sauer P239 pistol, is a backup emergency weapon used by law enforcement that has a light trigger mode and no safety. (The jury members asked to feel the trigger pull of the gun during deliberation, but the judge wouldn’t allow it, for reasons that aren’t clear to us.) The pixelated video footage of the incident that we were shown, taken from the adjacent pier, shows a group of six people spending half an hour at that same chair setting down and picking up objects a mere 30 minutes before Garcia Zarate arrived there.

There is a reasonable interpretation here that favors the defendant: He found the gun at the seat, picked it up out of curiosity, and accidentally caused it to fire. As a scared, homeless man wanted by immigration enforcement, he threw the gun in the water and walked away. The presumption of innocence, as stated in the jury instructions, required the jury to select this interpretation because it is reasonable and favors the defendant.

But why the manslaughter acquittal? Most of the confusion I've encountered has been over this part of the verdict, and it does seem to me personally that manslaughter is the appropriate charge for Steinle’s killing. However, given the evidence and the law presented in this trial, it is clear to me that the jury made the right decision.

The involuntary manslaughter charge that the jury was read included two key requirements: 1) A crime was committed in the act that caused death; 2) The defendant acted with "criminal negligence"—he did something that an ordinary person would have known was likely to lead to someone's death.

The jury members were not free to select the crime for part (1)—they had to use the one chosen by the prosecution, and the prosecution chose that crime to be the "brandishing," or waving with menace, of a weapon. As a juror, I found this choice puzzling, because the prosecutor presented absolutely zero evidence of brandishing during the trial. I don’t think we even heard the word “brandishing” until it was read as part of the charge during the jury instructions at the trial's end. No witnesses ever saw the defendant holding a gun, much less brandishing it. Given that baffling choice by the prosecution, the manslaughter charge was a nonstarter for the jury. Had a different precursor crime been chosen—for instance, the unlawful possession of a firearm by a felon—the outcome might have been different.

Even in that case, however, it is not clear to me that part (2) of the manslaughter charge was proved. Only a single particle of gunshot residue was found on the defendant’s hands, which seems to support his repeated claim that the gun was wrapped in some sort of fabric when he picked it up and caused it to fire. If he did not know the object was a gun, it is a stretch to claim that it was criminal negligence for him to pick it up.

The jury did convict Garcia Zarate of the separate charge of illegal possession of a firearm, which indicates that the members felt it to be an unreasonable conclusion that he didn’t know he was holding a gun. He was in the seat where he claims he found it for about 20 minutes prior to the shooting, and he made some statements during interrogation that seemed to indicate that he had known what the item was. Without the benefit of being able to re-examine the evidence during deliberation, I’m not sure that I would consider that evidence to constitute proof beyond a reasonable doubt, but knowing these jurors, I would trust them to have made an accurate judgment if the manslaughter charge had survived the first requirement.

I have come away from this experience with a strong sense of respect for the jurors and their objective handling of a sensitive case under the national spotlight. I hope that I would have acted with the same level of maturity.