One common argument often made by pro-firearm activists as a counter to blanket gun-control measures is that in order to curb gun violence, the solution is to have increased punishments on the process of gun smuggling, or possessing unregistered, illegal, or smuggled firearms.
The argument stems from the notion that a leading cause of gun-related homicide comes from gang violence, as gangs often source from or participate in the firearm black market. Gang-related gun violence also can lead to innocent civilian deaths. The argument proposes that significantly increasing the criminal liability of possessing or participating in these activities would be disproportionately more effective at reducing deaths than any blanket gun ban would.
The question is, does this proposal hold water? I haven't been able to find any data on places that have implemented this type of policy, or if it has lead to the theorized outcome.