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During the four years in which Donald Trump was president the first time, California sued him approximately every 12 days on average.

Now that he’s back in office, Democratic state leaders are preparing for potential new trials.

State Attorney General Rob Bonta has drawn up plans to defend California’s policies since summerwhen polls showed a high chance of Trump winning the election. Bonta said his team wrote preventive briefs on a variety of issues in preparation for what follows.

“During the previous Trump administration, California (the Justice Department) fought hard against Trump’s rollbacks and illegal policies that violated the rights of Californians … and would do so again if needed,” the attorney general’s office said in an unsigned email reply before the election.

California has sued the Trump administration 123 times and won major victories. Among them: California defended state clean air rules, retained Deferred Action for Childhood Arrivals program (DACA) that benefits undocumented people who came to the United States as children and protected the Affordable Care Act.

Those issues — the environment, immigration and health care — could once again be the main battle lines in the lawsuits expected to be fought between California’s Democratic administration and the Trump White House.

Govt. Gavin Newsom foreshadowed potential disputes in a statement on Wednesday.

“California will try to work with the next president — but make no mistake, we intend to stand with states across the nation to defend our Constitution and uphold the rule of law,” he said. “Federalism is the cornerstone of our democracy. It’s the United States of America.”

This time, some experts anticipate that Trump will present a more methodical approach to policy.

They point to Project 2025a 900-page document by the conservative think tank Heritage Foundation that sets out a conservative agenda. While Trump tried to distance himself from the project during his campaign, former members of his administration contributed to the report. There is also some overlap between what he proposed and what is outlined in the document, such as mass deportations and review of the Department of Justice.

Picking battles in a second Trump term

In his victory speech, Trump flagged policy goals that could conflict with California’s goals, such as expanding oil production and handing over the nation’s public health agencies to vaccine skeptic Robert F. Kennedy Jr. – though in what capacity is still unclear.

“He’s going to help make America healthy again,” Trump said of Kennedy during his speech. “I just said, ‘But Bobby, give me the oil.

“‘Bobby, stay away from liquid gold. Other than that, go have a good time.”

While Democratic leaders promise to uphold their values, this time they may be more careful in picking their battles, said Matt Lesenyie, a political science professor at Cal State Long Beach.

“Some of the legal challenges are fundamental, like we want to regulate greenhouse gases. Others may be more symbolic and not to trivialize cultural or gender identity, but one thing that has been clear, at least to me in this Trump victory, is that those cultural issues are driving his voters,” he said.

Because it is a large state, California also has the power to negotiate with the federal government.

“Faced with almost total Republican control of the federal government, Sacramento may believe the state is better off negotiating,” said David A. Carrillo, executive director of the California Constitutional Center at Berkeley Law. “This affects whether California’s strategy is to fight on all fronts or focus on leveraging its size and market power in striking its own domestic and international agreements — call it easy secession.”

Probably disputes over abortion, health care

In most cases, health care policies are expected to be challenged again.

In his first term, Trump’s efforts to repeal the Affordable Care Act failed, but he scaled back some provisions of the landmark health law.

He also influenced the reversal of Roe v. Wade, the 1973 decision that protected abortion rights by appointing three conservative Supreme Court justices.