Juan Francisco Lopez-Sanchez, the five-time immigrant deportee and seven-time convicted felon who shot and killed Kathryn Steinle in San Francisco last Wednesday, told ABC7 News that he came to the city because he knew it was a "sanctuary city" that would not deport him. Most Democratic presidential contenders have supported such sanctuary cities in the past, while many in the GOP field seem to be avoiding the issue, with the exception of Donald Trump.

Sanchez had already been deported back to his native Mexico five times, but he kept coming back "because I was looking for jobs in the restaurant or roofing, landscaping, or construction," he told ABC.

ABC added, "Sanchez said he knew San Francisco was a sanctuary city where he would not be pursued by immigration officials."

U.S. Immigration and Customs Enforcement (ICE) had arrested Sanchez for felony re-entry but eventually turned him over to the San Francisco sheriff's department, which had a warrant on him for drug charges. ICE placed a detainer request on Sanchez asking to be notified before his release so he could be picked back up by federal authorities and be deported. But due to San Francisco's sanctuary city policies, local police ignored both the ICE request and federal law and released Sanchez back onto the streets, where he went on to murder Steinle.

In another incident last Thursday in Laredo, Texas, another illegal immigrant, Juan Francisco De Luna Vasquez, allegedly murdered his wife with a hammer. He had been deported on four previous occasions and re-entered the States due to insecure borders. Vasquez was repeatedly brushed aside and ignored by Laredo police who refused to notify Border Patrol, according to officials who spoke to Breitbart.

Had local police enforced federal law and contacted immigration authorities regarding the status of the illegal immigrants, both murders could have likely been prevented.

And yet all four of the Democratic presidential candidates have expressed support for sanctuary cities that protect potentially dangerous illegal immigrants from deportation.

Vermont Sen. Bernie Sanders and former Virginia Sen. Jim Webb both previously voted against an amendment that would have blocked federal funds from being allocated to sanctuary cities. And last year, Maryland Gov. Martin O'Malley announced that Baltimore city jails would stop honoring ICE requests to hold illegal immigrants until they could be deported, choosing instead to release them back into the streets, according to The Daily Caller.

Former Secretary of State Hillary Clinton last voiced public support for sanctuary cities during the 2008 presidential campaign, when she said that she doesn't think there is any choice but to allow sanctuary cities to disobey federal law. Without sanctuary cities, illegal immigrants would refuse to cooperate with police out of fear of being deported, Clinton told Tim Russert during a September 2007 debate at Dartmouth College.

Clinton then reaffirmed to Fox's Bill O'Reilly in 2008 that she has no plans to crack down on sanctuary cities.

Jessica Vaughan, a policy director at the Center for Immigration Studies, told The Daily Caller that Clinton's statements indicate "that she intends to outdo the Obama administration in dismantling immigration laws, so there is good reason to be concerned that this problem would get worse under a Clinton administration, and that more local governments would either be encouraged or coerced into obstructing ICE."

"I would expect another Clinton administration to stoop to the same kind of legal hi-jinks, abuse of authority, disregard of safety and security, and then evasion of accountability, much as we witnessed when she was Secretary of State," Vaughan added.

As for the GOP presidential field, Trump appears to be the only candidate willing to hit hard on the failed immigration policies which led to Steinle's murder, as most candidates desperately need the Latino vote and are treading lightly on the issue.

"Where are the other candidates now that this tragic murder has taken place b/c of our unsafe border ... We need a wall!" Trump tweeted.

Trump called the murder a "senseless and totally preventable act of violence" which serves as "yet another example of why we must secure our border immediately," according to CNN.

He continued: "This is an absolutely disgraceful situation and I am the only one that can fix it. Nobody else has the guts to even talk about it. That won't happen if I become president."