Do laws in their own and neighboring states counter the efforts of various US cities efforts to regulate firearms?

The effect of cities’ attempts to regulate firearms locally can be limited by state laws enacted in their own as well as neighboring states.

Forty-two states have laws “pre-empting” local governments from adopting their own specific gun-control measures, despite what may be strong local support.

In states with stronger controls, recent research finds those can be offset by weaker regulations in nearby states. More liberal rules in neighboring states correlate with increased rates of total firearm deaths, suicides and homicides within a state. Conversely, proximity to states and population centers with stronger gun laws was correlated with lower homicide rates.

In Baltimore, 82% of guns seized by police last year were obtained outside the city—63% outside Maryland. Some 60% of firearms seized in Chicago over the years 2013 to 2016 came from other states with more permissive laws.