Arizona Attorney General Kris Mayes has announced the state is withdrawing from a multistate lawsuit challenging federal efforts to regulate so-called “ghost guns.”

The rule by the Bureau of Alcohol, Tobacco, Firearms, and Explosives changes the definitions of “firearm” to make clear that privately made firearms and “ghost guns” are included. 

Ghost guns are unregulated firearms that anyone can buy and build without a background check. 

They’re also unserialized and untraceable. Mayes’ predecessor filed the lawsuit in July of last year. 

In a statement Friday, Mayes said she believes the rule is within the bureau’s authority and provides much needed regulation.

The case is now pending in the 8th Circuit Court of Appeals.