(San Antonio, TX) — The battle over a state probe into the citizenship status of tens of thousands of registered voters moves to federal court as of today.

Civil rights groups are suing to shut down the investigation, calling it a threat to voting rights.  Lawyers for Texas Attorney General Ken Paxton will ask the judge to toss out the lawsuit.  They claim it mis-characterizes the probe, which is required by law, as an attempt to purge voter rolls.

Today’s hearing in San Antonio will likely focus on the investigation’s potential to harm legally registered voters.