Those rules were also halted for the rest of the country on Monday when a Pennsylvania judge granted a nationwide injunction in a similar lawsuit.

The contraception case is one of several fronts where Becerra has led state coalitions to defend the Affordable Care Act in lawsuits in Texas, California and Washington, D.C.

“The Trump administration is trying to chip away at those protections,” said Andrew Kelly, an assistant professor at the Department of Health Sciences at California State University-East Bay. “It's left to states like California and Attorney General Becerra in taking a lead in confronting these efforts.”

Becerra is perhaps best known for leading the opposition to the Texas v. U.S. lawsuit. In that suit, the Texas attorney general argued that the Affordable Care Act should be rendered unconstitutional because Congress eliminated the tax penalty on the uninsured. A federal judge last month sided with Texas, ruling that the federal health care law is unconstitutional.

Becerra, who said he helped write the health care law, said he felt compelled to step in when the Trump administration decided not to defend the law. Sixteen states and the District of Columbia joined that lawsuit, which is now on appeal.

The multistate strategy is one that attorneys general have used often in the past few decades when they don't agree with policies coming out of Washington, legal and political experts say. And it's not unique to one political party.

Republican attorneys general, for example, sued the Obama administration to block the expansion of Medicaid in their states. When George W. Bush was president, the state of Massachusetts led Democratic states in an effort to force the Environmental Protection Agency to regulate greenhouse gas emissions from cars.

The legal tit for tat is what Nicholas Bagley, a professor at the University of Michigan Law School, described as a disconcerting “militarization” of the state attorneys general offices to press an agenda in the courts.

“At a time of polarized politics, there's every incentive to pull whatever levers are available to you to try to advance your goals,” Bagley said. “Over time, the state attorneys general have come to the view that the courts are an important forum to have these fights over important questions.”

The behavior of the attorneys general also comes in response to an administration that is using its executive authority to push initiatives that it can't get Congress to approve.

President Donald Trump is left “to try to use either the regulatory process or executive order to accomplish his goals,” said Gerald Kominski, a professor of health policy at UCLA. “Anyone who opposes those goals has to proceed through the legal process to challenge them.”

Becerra, the first Latino to serve as California attorney general, has sued the Trump administration on a wide range of issues: health care, immigration, the Muslim travel ban, citizenship questions on the census, the border wall, climate change and clean-water rules.

When the former congressman was sworn in to his second term last week, he declared that he had “been a little busy keeping the dysfunction and insanity in Washington, D.C., from affecting California,” and defending the state from the “overreach of the federal government.” And he doesn't have any plans to let up.

“Whether it's the criminals on our streets or the con man in the boardrooms or the highest office of the land,” Becerra said, “we've got your back.”

But Becerra's record has been mixed.

The victory in court Sunday was limited. Oakland-based U.S. District Judge Haywood Gilliam Jr. blocked the rules from taking effect in the District of Columbia and the 13 states that challenged them, but he refused to stop them from taking effect in the rest of the country. That national reprieve came a day later in a Pennsylvania court, with U.S. District Judge Wendy Beetlestone describing the harm to women as “actual and imminent.”

If the administration appeals, as expected, Pennsylvania, along with California and its legal coalition would move ahead with their cases to permanently throw out the rules, arguing that the Affordable Care Act guaranteed women no-cost contraception as part of their preventive health care, a provision that they say has benefited more than 62 million women since 2012, when the regulations went into effect.

The Trump rules, California argued in legal filings, would “transform contraceptive coverage from a legal entitlement to an essentially gratuitous benefit wholly subject to an employer's discretion.” In its proposed regulations, the U.S. Department of Health and Human Services described the exemption as narrow and one that would affect a fraction of women — no more than 127,000.

That's a number Becerra disputes.

In claiming victory on the birth control lawsuit, Becerra said Sunday that his coalition will continue to advocate for women's access to reproductive health care.

How much more will Becerra fight during the next four years? Addressing the crowd who gathered this month to see him sworn in to a second term, he conveyed a simple response:

“The sky is the limit.”

Kaiser Health News is a nonprofit news service covering health issues. It is an editorially independent program of the Kaiser Family Foundation, which is not affiliated with Kaiser Permanente.

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