....No one, other than the supervision of the people entering data into the system is in any position to see to it that the data entered is complete and correct. And, even when those people are all diligent, mistakes and errors still happen.....
I remember hearing of a situation one time where the police were going to arrest a guy for possession of a stolen gun. It was his own gun. But it was on the list as being stolen. S&W .38 caliber revolver ser#XXXXXX....
That was the information the cops had. The guy involved had more info. He had the receipt proving that he had purchased the gun, new, from an FFL dealer several years before. It did, however match perfectly the information the cops had. BUT it wasn't the same gun. The police were, (at the time) not aware that S&W used the same serial number sequences on several different models of guns, and that a 2" .38 S&W could have the same serial#XXXXXX as a 6" .38 SPECIAL revolver manufactured 3 decades later....