Pittsburgh Mayor Bill Peduto on Tuesday signed four gun control laws, setting up a fight over the limits of municipal authority over the regulation of firearms in Pennsylvania.

Following the mass shooting at the Tree of Life Synagogue in October that killed 11, the Pittsburgh city council passed a series of gun control regulations aimed at reducing the availability of assault-style weapons. Peduto’s signature on the laws effectively bans automatic assault rifles in the city, along with banning armor-piercing ammunition and high capacity magazines. In addition, the laws strengthen “red flag” provisions that allow courts to seize firearms from people who are deemed a danger to themselves or others by the local courts.

The District Attorney for Allegheny County, Stephen Zappala Jr, advised the city council that Pennsylvania law doe not permit municipalities to regulate firearms. It is expected that the laws will be challenged in state courts, a fight that Peduto welcomes. In an interview with NPR, Peduto stated “there is a big difference between legality and justice, and in order to be able to make laws just you have to challenge existing laws.”