The man, Juan Francisco Lopez-Sanchez, has been charged in last week's shooting death of Kate Steinle on one of San Francisco's busiest piers. He's a repeat felon who has been deported to Mexico five times
, according to immigration officials.
Mayor Ed Lee said Lopez-Sanchez should never have been back on the street.
"Nothing in that law prevents or prohibits communication, notification with our federal and state law enforcement officials," Lee said at a Wednesday news conference. "Is this a gap? Do I need to educate somebody about how to pick up a phone?"
San Francisco County Sheriff Ross Mirkarimi said he was under no obligation to call immigration officials.
"The mayor would be subverting, sabotaging his own law ... that was passed by the Board of Supervisors and that he signed into effect in 2013," Mirkarimi told CNN affiliate KGO-TV
"It's very clear that it stipulates to law enforcement, in this case the sheriff's department, that a notification detainer request should not be returned unless ICE (Immigration and Customs Enforcement) also provides a court order or a warrant."
Because the feds didn't come with either, he let the accused killer go. Immigration officials had only requested that the sheriff's office let them know when Lopez-Sanchez was released.
Politics of immigration
The case has drawn the attention of presidential candidates and brought a renewed focus on U.S. immigration laws and the role local authorities should play in enforcing them.
The key question is whether San Francisco's policies set the stage for the shooting by putting a criminal on the streets instead of delivering him into the hands of federal authorities who could have deported him again.
In an interview Tuesday with CNN
, Democratic presidential hopeful Hillary Clinton said San Francisco should have listened and made a mistake when it didn't send Lopez-Sanchez packing.
"I have absolutely no support for a city that ignores the strong evidence that should be acted on. ... If it were a first-time traffic citation, if it were something minor, a misdemeanor, that's entirely different," she said. "This man had already been deported five times. And he should have been deported at the request of the federal government."
Immigration and Customs Enforcement said Lopez-Sanchez has seven felony convictions, four for drug offenses. His most recent deportation was in 2009.
On Tuesday, Lopez-Sanchez pleaded not guilty to murder and weapons charges. His bail was set at $5 million.
The gun used in the killing was stolen from a vehicle belonging to a federal Bureau of Land Management agent, a source familiar with the investigation said Wednesday.
Still, investigators are trying to determine how Lopez-Sanchez allegedly obtained the .40-caliber pistol, according to the source.
The Bureau of Land Management said the service weapon was stolen from the officer's vehicle on June 27. Steinle was shot and killed July 1.
Lopez-Sanchez told CNN affiliate KGO-TV
that he fired the weapon, but it was an accident. He said he'd found the gun wrapped inside a T-shirt before it accidentally went off.
It was not clear whether Lopez-Sanchez understood all the questions posed in English and Spanish during the KGO interview. He appeared disoriented and gave contradictory answers about what had happened and how he felt