The Justice Department on Wednesday released guidance intended to caution states embarking on so-called post-election ‘audits’ of vote counts for the 2020 presidential election that they must not run afoul of federal voting laws.

The guidance, previously previewed last month by Attorney General Merrick Garland in his policy address on voting rights, outlines federal statutes that the department says elections officials must adhere to during such “audits,” such as preserving all federal elections materials and making sure they’re not tampered with.

“This document sets down a marker that says the Justice Department is concerned about this, and we will be following this closely,” a DOJ official told reporters on a media conference call Wednesday.

The guidance echoes a warning sent by the department back in May to the Republican-run audit in Arizona, warning officials there that all election records must be preserved and expressing concern about the state handing over election materials to the private contractor group Cyber Ninjas.

After the department’s letter, Arizona officials backed off of a plan to send contractors from the group to visit homes in the state’s largest county of Maricopa to ask voters whether or not they had cast ballots. The Wednesday guidance includes a warning that officials who seek to embark on such “audits” can’t do so in a way that will intimidate voters.

DOJ officials on Wednesday declined to provide any update on the department’s review of the Arizona “audit.” But the guidance comes as Republicans in several other states have expressed interest or are already moving forward with similarly partisan reviews of the 2020 vote count in certain jurisdictions — despite lacking any evidence of widespread fraud.

The department also issued separate guidance Wednesday that outlines the range of federal laws protecting voting by different methods.

“It’s responsive to the fact that more Americans than ever are voting, not on Election Day in person in a polling place, but that are voting at voting centers or voting early or voting by mail,” one official said.

An official said that the second set of guidance should be a note of caution to states that might be looking to roll back policies that expanded access to voting during the COVID-19 pandemic. The official gave the example of the election bill passed this year by Republicans in Georgia that implemented voting restrictions the department is now suing over, alleging it unlawfully targets minority communities.

“You should not assume that if you abandon the practices that have made it easier for people to vote, that abandonment is not going to get scrutiny from the Department of Justice,” an official said.