Tax gun manufacturers for the murders committed with their weapons.

Trace gun murders to the gun's manufacturer. Tax the manufacturer $10 Million per murder, which can go to the general treasury of the United States. Require gun manufacturers to insure themselves to pay this tax. Insurance analysts can estimate how many deaths each gun model will cause, and charge premiums accordingly. The cost of a gun will reflect the likelihood that that model will be used murder someone. Honest gun users will demand guns with safety features that prevent mass killings, since those guns will be cheaper to insure. The free market will determine the value of guns, taking the toll on human lives into account. Gun owners should support this.