Gov. Jan Brewer signed legislation Monday that bans cities and counties from destroying guns turned over to police at community buyback events.
The law requires instead that the guns be resold.
Republicans and the National Rifle Association supported the legislation, while Democrats opposed it.
Tucson and other cities have destroyed weapons turned in at buy-back events, arguing it was legal because the guns were voluntarily surrendered.
Tucson City Councilman Steve Kozachik sponsored a gun buy-back in January at which 206 guns were turned in. The gun owners got $50 gift cards to a store in exchange.
Police said many of the guns that were turned in were old and some did not function. one gun had its serial number rubbed off, and police said they would investigate.