The suspect in that case, 21-year-old Salvadoran immigrant Edwin Ramos, reportedly was protected by San Francisco's recently rescinded "sanctuary city" policy. Under the policy, San Francisco did not share information about undocumented criminals with immigration officials, who could have deported Ramos due to prior offenses.
Mountain View and Santa Clara County do not have a sanctuary policy, making it harder for someone like Ramos — who had juvenile court convictions for violent crimes, including a gang-related assault — to avoid the notice of immigration officials. Still, although it's less likely, violent criminals can skirt deportation here. Interviews with local police and county prosecutors indicate that there is no formal policy on when to report a suspect's immigration status, and police say they don't ask the question upon arrest.
As a result, federal immigration officials often end up screening local jail populations, but it's an overwhelming job, and not a top priority due to the war on terror, according to U.S. Immigration and Customs Enforcement, or ICE.
The county district attorney's office has an unwritten policy of reporting the immigration status of violent criminals, including juveniles, but "Unless they [the criminals] tell us there is no way to know," said Javier Alcala, supervising deputy district attorney for North County.
"Our office can report to ICE either when someone has been charged with a crime, or after conviction," said Amy Cornell, spokesperson for the district attorney's office. "It happens on a case-by-case basis. It's more common for arresting agencies to report immigration status."
In Mountain View, police "generally do not ask" for a suspect's immigration status, said retired police captain Bruce Barsi.
Police spokesperson Liz Wylie said the question isn't even on the booking forms that the county supplies to local police departments.
"We don't ask that question of people we arrest," Wylie said. "We ask where people are born but that doesn't imply immigration status. We treat everybody the same. In a very specific situation or problem, we reserve the right to contact [ICE]."
But policies and practices can change, as they did recently in San Francisco, which has begun turning over to immigration officials a number of juvenile offenders released from its jails.
"Every city has the same issue as San Francisco," said Mayor Tom Means. "I don't think we are going to go around and ask, 'Are you legal or not?' I don't think that's appropriate. A lot of it would have to do with what type of crime is being committed. You would have to look at that and come up with a policy in terms of severity."
"It would be very hard to have a policy for all the things you would run into," Barsi said.
"Our agents are highly trained in their ability to get to the bottom of things," said Tim Counts, public affairs officer for Immigration and Customs Enforcement. But like any other law enforcement agency, Counts said, "Our resources are limited. National security concerns get our attention first. We are not omnipresent."
Counts added that ICE is usually not interested in deportation until after jail time has been served.
Cornell said there are no records on how many undocumented criminals are deported in Santa Clara County. However, Wylie said that when she worked as a detective in Mountain View's sex crime unit, ICE notified her several times a year when a sex offender in Mountain View was going to be deported.
"If you are a child molester, rapist or a murderer we are not going to protect you from ICE," Wylie said.
Former gang members have told the Voice that the city's gang members are predominantly Surenos, or "Southerners," who have recently immigrated or whose parents have immigrated from Central or South America.
Police say that the vast majority of immigrants from Central and South America are not violent criminals of any kind. The Mountain View Police Department continues to have a policy of not helping ICE with raids that aim to capture and deport the many undocumented workers who are working and living peacefully in the U.S.
Last year, police Chief Scott Vermeer stated that his department has "no role enforcing federal immigration laws ... unless the safety of the general public is at stake." He added that "all emergency services are totally disinterested in immigration status."