The U.S. Department of Justice cautioned states on Wednesday that undertaking partisan election audits like the one underway in Arizona could violate federal law, sending a warning shot to states as more Republican state lawmakers move forward with their own controversial probes.

The DOJ’s new guidance document explicitly warns against audits in which election officials are forced to turn over materials like ballots or voting machines to state lawmakers or third parties—as in Arizona, whose audit is being run by the private company Cyber Ninjas.

Federal law requires state and local election officials to retain federal election records for at least 22 months after an election, and the DOJ said it interprets the Civil Rights Act to mean “elections records [must] ‘be retained either physically by election officials themselves, or under their direct administrative supervision.’”

Violating federal law by turning over election materials could be punishable through fines of up to $1,000 or a prison sentence of up to one year. While some audits could comply with state law, the DOJ said, “federal law imposes additional constraints with which every jurisdiction must comply.”

Taking election materials out of election officials’ control carries a “significant risk of the records being lost, stolen, altered, compromised, or destroyed,” the DOJ wrote. The federal government had previously warned the Arizona audit could be in violation of federal law, but their guidance Wednesday extends that warning to all states considering similar probes.