The Justice Department is throwing its weight behind a federal lawsuit led by the City of Huntington Beach and Riverside County Sheriff Chad Bianco, arguing that California’s 2017 “sanctuary” law violates the supremacy clause of the U.S. Constitution by blocking local law enforcement from cooperating with federal immigration authorities.

In a 36-page statement of interest filed last week, the Trump administration’s DOJ called California’s law, known as the California Values Act, “unlawful” and asked a federal judge to rule in favor of Huntington Beach’s challenge.