On Tuesday night, just after completing a roundup of more than 150 suspected undocumented immigrants, U.S. Immigration and Customs Enforcement said it could have arrested more but for the actions of one person: Mayor Libby Schaaf of Oakland, Calif.

Schaaf learned of the Northern California ICE enforcement operation before it kicked off on Sunday and, in a controversial move, warned the immigrant community ahead of time.

On Saturday, saying she felt it was her moral and ethical duty, she stood in front of television cameras and announced that “multiple sources” had informed her that ICE would be making arrests across the Bay Area. She didn’t intend to panic the community, she said — only to protect it.

ICE Deputy Director Thomas D. Homan, however, had a different idea of what she was trying to do, saying on Tuesday that he believed some of the 864 “criminal aliens” that still remained at large “were able to elude us thanks to the mayor’s irresponsible decision.”

“Sanctuary jurisdictions like San Francisco and Oakland shield dangerous criminal aliens from federal law enforcement at the expense of public safety,” Homan said in a statement. “The Oakland mayor’s decision to publicize her suspicions about ICE operations further increased [risks] for my officers and alerted criminal aliens — making clear that this reckless decision was based on her political agenda with the very federal laws that ICE is sworn to uphold.”

Schaaf is unapologetic.

In an interview with The Washington Post on Tuesday, she explained that her decision to tip off immigrants stemmed from a deep disagreement with immigration enforcement under the Trump administration and a resistance to the administration’s enforcement efforts.

She had already made her defiance clear last month when she told reporters that she was willing to go to jail to defend Oakland’s “sanctuary city” policy of protecting immigrants who are in the country illegally and not cooperating with federal authorities to deport them. She said Tuesday that she was responding to a suggestion from Homan in January that the Justice Department should begin criminally charging California politicians who supported sanctuary jurisdictions. Politicians like her, she said.

Asked by The Post whether she considered herself part of “the resistance” movement — the unofficial title for left-leaning Americans who do not support the Trump administration — she responded with a resounding yes.

“I consider myself a law-abiding citizen. I consider myself a believer in an American democracy that moves towards a more just society. And I definitely consider myself part of the resistance,” she said.

As Schaaf decided whether to warn the community Saturday, she said she was thinking of the case of Maria Mendoza-Sanchez, a 46-year-old mother of four and nurse at an Oakland hospital, who, along with her husband, was deported to Mexico after more than 20 years in the United States. Neither she nor her husband had criminal records, as the San Francisco Chronicle reported.

Neither did roughly half of the suspected undocumented immigrants rounded up in ICE’s latest North California operation — which, Schaaf said, is what she had feared.

“Maria Mendoza-Sanchez and her husband are an example of a couple that, under the previous administration, were considered low-priority for deportation,” Schaaf said. “And under this administration they were ripped away from their family. I was absolutely thinking of them when I made the decision to share the [ICE enforcement] information. I think it’s my responsibility as a person in power and privilege to share the information I have access to, to make sure people know what their rights are.”

Schaaf had first started fighting against such deportations as a lawyer, before the idea of public office had even crossed her mind, she said.

After graduating from Loyola Law School in Los Angeles, the Oakland native started her career as a lawyer at Reed Smith, a large corporate law firm where she did some work on deportation cases on a pro bono basis. The last case she worked as a lawyer involved a Salvadoran man seeking political asylum, after he had seen his girlfriend raped by soldiers, Schaaf said, and after his home burned down in a fire that killed his baby.

“It’s part of what makes me have such deep respect for so many of the immigrants who come to Oakland,” she said, “who have been through unspeakable hardships. At the time I defended him, we were the exact same age — not even 30 years old — but had led such unbelievably different lives.”

Schaaf soon moved on to co-found a volunteer organization called Oakland Cares, which coordinated various public-service projects around the city, and to spearhead another volunteer group working on projects within Oakland public schools. She took her first job as a city official as an aide to the president of Oakland City Council.

She moved up to work as an aide to then-Mayor Jerry Brown, who went on to become governor, before successfully running for the city council herself. She ran successfully for mayor in 2014, garnering 63 percent of the vote.

Oakland, like its Bay Area neighbors Berkeley and San Francisco, is a bastion of progressive politics. Previous mayors, in addition to Brown, have included former Democratic Rep. Ronald V. Dellums and the first Asian American woman mayor of a major city, Jean Quan.

Under Schaaf’s administration, Oakland has raised the minimum wage to $12.25 an hour, developed the city’s first transportation department and created a “cradle-to-career” initiative designed to shepherd children born into poverty to college.

Her tenure has not been without controversy. Just after taking office in 2015, protesters with Black Lives Matter held a rally outside her house complaining that she was prioritizing meetings with scandal-entrenched police officials over meetings with Black Lives Matter advocates.

A year later, a group called the Anti-Police Terror Project called for her removal from office over those police scandals and escalating tensions between police and communities of color, saying Schaaf was not seeking solutions.

Just last month, another protest sprouted up outside her home, this one from homeless advocates saying Schaaf was not doing enough to further low-income housing, despite her administration saying it was a priority.

Schaaf said she has respected the viewpoints of those criticizing her.

“I’ve lived in Oakland my whole life, and Oakland has always been a center of social justice,” Schaaf said. “In Oakland, the level of activism is so high that anyone in a position of governmental authority is going to be questioned and challenged, and I celebrate that. It’s part of our democracy that people speak truth to power, and in Oakland, that is a particularly time-honored tradition.”

It was social justice that was on her mind when she tipped off the immigrant community about the ICE raids.

Schaaf has said that she consulted her legal counsel before deciding to act. Because she obtained the information from unofficial sources rather than through formal government channels, she doesn’t believe she obstructed justice or violated any law by speaking up.

Critics disagree. Tony Brass, a former federal prosecutor told CBS in San Francisco that “she’s on the threshold of obstruction of justice for doing what she did … because you put agents in danger. You put the police in danger and you put your neighbors in danger.”

Maricela Gutiérrez, executive director of the immigrant-advocacy organization SIREN, said that at first reactions within the immigrant community were mixed after Schaaf announced the raid. There had been panic, she said, and a lot of questions: How did the mayor get this information? How does she know it’s really going to happen?

Still, Gutierrez said, she and her colleagues took the opportunity to alert the community and provide resources about their legal rights if they were confronted by ICE.

“It really created a mass mobilization,” she said. “As advocates, we took [Schaaf’s warning] very seriously. When do you hear a mayor of a big city announcing that an ICE attack is going to happen? Never. If she’s saying that, it must be true.”

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