The Arizona Supreme Court is set to hear arguments over the constitutionality of a 2016 law allowing the state to withhold funding from cities that have ordinances conflicting with state laws.
The case stems from a Tucson policy to destroy guns seized by its Police Department.
Arizona Attorney General Mark Brnovich argues that may violate a 2013 law requiring them to be sold.
Tucson's lawyers says the 2016 law sets up cities to be investigated and penalized for violating state law and is unconstitutional.
