Washington (CNN)A California local elected official is shaping up to lead the charge as the state wages legal and political battles against the Trump administration: Oakland Mayor Libby Schaaf.
Who is Libby Schaaf, the Oakland mayor called out by Sessions
Schaaf, who has served as the city's mayor since 2015, has not shied away from attacking President Donald Trump's stance on immigration, and for that, she has garnered both attention and backlash.
Here's what you need to know about the Golden State politician.
Schaaf grew up in a more affluent residential area of Oakland called Oakland Hills.
She served as a lawyer for two years before turning her attention to politics. She worked as an aide to Gov. Jerry Brown when he was the mayor of Oakland, and he later endorsed her mayoral campaign.
Given the expansion of tech companies to the Oakland area -- including ride sharing giant Uber -- creating affordable housing has been a huge priority for Schaaf.
Still, some Oakland residents don't think she's doing enough on that front. A local ABC station reported in January that protesters camped out at her home to advocate for more affordable housing.
She also was serving as mayor during the fatal Ghost Ship fire in 2016, which killed 36 people who were at the two-story warehouse and artists' studio for a party when the blaze broke out.
That same year, the Oakland Police Department was at the center of a massive sex abuse scandal that made national headlines.
"There is hardly a day that goes by as mayor of Oakland that I'm not met with some unpredictable challenge," Schaaf told the Los Angeles Times in 2016.
She is running for office again in November.
Schaaf has been garnering national attention for her stance on immigrants rights.
She came under scrutiny in February, after she warned her community of imminent raids by US Immigration and Customs Enforcement agents in the San Francisco Bay Area.
She issued a warning on Twitter and held a news conference the next day.
"I am sharing this information publicly not to panic our residents but to protect them," she said. "My priority is for the well-being and safety of all residents -- particularly our most vulnerable."
For that, she came under heavy criticism from ICE.
ICE Deputy Director Thomas Homan said Schaaf's warning had the opposite effect, because more than 800 immigrants with criminal records were at large in the community.
Schaaf pushed back on ICE's criticism and stood by her decision to make the warning.
"We have to fight against the racist myth that the Trump administration is trying to perpetuate -- that immigrants are dangerous criminals," she said.
The Trump administration on Tuesday announced it would sue the Golden State over its laws that seek to shield the undocumented from federal immigration authorities -- so-called "sanctuary state" laws.
"We will continue to exercise our legal right to exist as a sanctuary city," Schaaf said in a statement on the lawsuit. "We will continue to inform all residents about their Constitutional rights, and we will continue to support California's sanctuary status."
During a speech in Sacramento on Wednesday, Attorney General Jeff Sessions lit into Schaaf.
"How dare you?" he said. "How dare you needlessly endanger the lives of our law enforcement officers to promote a radical open-borders agenda?"
Trump also called out the mayor's actions.
"What the mayor of Oakland did the other day was a disgrace," Trump said Thursday. "They had close to a thousand people ready to be gotten, ready to be taken off the streets ... they say 85% of them were criminals and had criminal records. And the mayor of Oakland went out and warned them all."
Trump will make his first trip to California as President next week. White House press secretary Sarah Sanders confirmed the trip, but did not provide more details.