The machine to read the "gun fingerprint" was broken for almost a decade. The state police never bothered to fix it because they already knew it was forensically useless when it broke. Nonetheless, they kept collecting the casings as per law. The cost passed on to the gun buyer was about $10 per gun so it was an very slight financial block on gun buying. The legislators knew this so they took their time in repealing the law. It was an arbitrary and capricious tax on a constitutional right.