The Ninth Circuit has directed a lower court to preliminarily block California’s “No Vigilantes Act,” concluding the federal government is likely to succeed on its claim that the state law impermissibly regulates federal officers. The ruling is an important early win for the United States in a closely watched dispute over the limits of state power when legislating around federal immigration enforcement.

The statute would have required federal agents to display visible identification while carrying out their duties.

California and New York have opened a significant new front in the legal fight over federal energy policy, suing the Trump administration over plans to buy back offshore wind leases. The states argue the federal government is acting unlawfully by attempting to unwind existing lease rights in a way that undercuts offshore wind development and disrupts long-term clean energy planning.

At its core, the dispute is about the limits of executive power over federal energy programs.

The Justice Department has filed suit against New Jersey, Gov. Mikie Sherrill, and Attorney General Jennifer Davenport, alleging that the state’s “Law Enforcement Officer Protection Act” unlawfully restricts federal law-enforcement activity. The case, filed in federal court in New Jersey, tees up a direct confrontation over the limits of state power when federal officers operate within state borders.

At the center of the dispute is a familiar constitutional fault line: whether a state may regulate, constrain, or impose conditions on federal officials carrying out federal duties.