Maryland has a law for over a decade that says each new handgun sale must be accompanied with a spent shell that’s then forwarded to the state police upon purchase. The theory is that a case can be used to ID the gun and, from that, the owner.
Not one single case for any gun crime in Maryland has been able to use that connection as evidence leading to a conviction. Not one single case. There have been several cases which led investigators to an original owner, but those owners had nothing to do with the crimes.
That’s pretty stupid, I guess the pols in Maryland aren’t aware of the fact that firing pins change their primer imprint with enough usage. Or of course, the fact that one can just buy or make a new untraceable pin.