NEW YORK (AP) — A lawsuit filed Thursday challenges the Trump administration's sprawling effort to collect and analyze Americans' voter data, alleging the government has obtained voter files from at least 47 states and handled the data in a way that violates federal law.

The 42-page complaint filed in federal court in Washington, D.C., claims the Department of Homeland Security's secretive probe of the voter data, including a policy to combine it with commercial datasets, disregards federal safeguards and flouts the privacy rights of millions of Americans.

The case, brought by the League of Women Voters, the Electronic Privacy Information Center and the League of United Latin American Citizens, is the latest in a torrent of legal challenges that have emerged in response to President Donald Trump's crusade against noncitizen voting, a concern he views as a serious problem but which research shows is exceedingly rare.

The Trump administration has consistently sought to exert more power over elections, even as the Constitution grants that authority to states and, in some cases, Congress. Judges have consistently upheld states’ rights to decline to hand over their lists to the federal government.

DHS didn’t immediately respond to a request for comment.

Thursday's lawsuit alleges the Trump administration has obtained voter lists from 47 states, even as 30 states refused to turn them over to the administration. It calls for the court to declare the administration's collection of voter data illegal, block the policy and order DHS to delete and stop using the voter information it already has collected.

The lawsuit comes less than three weeks before Election Day, as the administration has continued to escalate threats to states alleging they are not doing enough to remove noncitizens from their voter rolls.

On Thursday, the administration sued California election officials, alleging they didn't act quickly enough to review names the federal government identified as “likely” noncitizens, and asking a judge to bar the state from counting those people's mail ballots for next month's midterm elections. The secretary of state's office said it was given just 48 hours to review 20,000 names without the Justice Department providing any evidence to substantiate its claims.