Create a NO-BUY list to prevent gun purchases by dangerous persons, as the NO-FLY list prevents hijackers on airliners.

Create a NO-BUY list for potential gun purchasers that government agencies consider unsafe. Instead of requiring each person to apply for permission to buy a weapon and, thereby, giving up their anonymous ownership, the government should create the list of persons BARRED from ownership. This list should be made available to anyone to enter the basic information of a potential purchaser to see if they are on the list, starting with a name, then DOB, then State DL, etc, If the person does show in the list, continue to enter delineating information until the individual is clearly identified or eliminated as a person listed.. Enumerate the reasons why a person would be placed on this list with a method for challenging the persons inclusion.
This would not need a new law to be passed.