Immigration officials have said they want to deport him. García Zarate affirmed that the shooting was accidental.
Remains in state custody, according to the indictment.
Federal charges were announced through a press release from United States Attorney General Jeff Sessions, US District Attorney for the Northern District of California Brian Stretch and Jill Snyder, special agent in charge of the Office of Alcohol, Tobacco, Firearms and Explosives.
Garcia Zarate, who is from Mexico and has been deported from the United States five times, faces up to 1
García Zarate's defense lawyers said Monday they will appeal the state charge for which he was convicted. They believe that the conviction for possession of weapons seemed to be in disagreement with the acquittals, given that those verdicts coincided with the defense that García Zarate found the gun by chance in the dock where the shooting occurred.
In final arguments, the lead attorney Matt Gonzalez argued that momentary possession, especially when you do not know what you are possessing, it is not a crime.
CNN contacted García Zárate's lawyers on Tuesday, but did not receive an immediate response.
DA takes the blame for acquittals
George Gascón, district attorney for the city and county of San Francisco, did not comment on the events, but spoke with reporters about the recent judgment.
Last week was not a verdict what we expected. We believe that this was a homicide, "he told a news conference on Tuesday.
Citing an ongoing lawsuit, Gascón refrained from discussing details about the case and assumed responsibility for any failure to prepare the case and the verdict. of no guilt.
"Since the day the murder occurred, (the) case has been used as a political trick," said Gascón.
She continued, "It hurts me to see politicians and candidates use the tragedy of this event to obtain political benefits. "
Gascon called Trump, saying that" we should not allow a tweeting madman to dictate everything we do "when he talks about the influence that politics has had on Steinle's trial.
Prosecutors said Garcia Zarate deliberately shot at an unsuspecting crowd at the dock in July of 2015, and killed Steinle while walking with his father.The defense said the gun exploded by accident, and the bullet bounced on the ground and traveled about 80 feet before hitting Steinle.
García Zárate was charged with second-degree murder, but juries were allowed to consider first-degree murder and involuntary manslaughter.
The jury deliberated about six days before issuing its decision.
Trump called the verdict "shameful," while Sessions said that the San Francisco state as a sanctuary city was largely to blame for what happened.
Dan Simon and Eric Levenson of CNN contributed to this report.