Why, there oughtta be a law. That's why Senate Majority Leader Malcolm Smith (D, naturally), "announced a program to curb illegal guns." He did not reveal how he intended to make sure violent career criminals cooperated, however.
But don't worry, because Nassau County District Attorney Kathleen Tice has just the "common sense" ticket: Microstamping.
With microstamping, the gun's firing pin would imprint a unique ID number on each shell casing, which could link that weapon to a crime.
Yeah, except there are already something like 200 million guns already in this country that will not be affected, it won't be applied to guns in any of the other states, it won't happen with rifles, shotguns or revolvers, firing pins can be filed down or replaced, stolen guns won't tell you who committed the crime, ejected brass can be picked up by the perp, and brass picked up from firing ranges can be "seeded" at the scene to throw investigators off track and implicate the innocent.