Columbia subject headings:
Criminal records--United States.
Firearms ownership--United States.
Firearms--Purchasing--United States.
Gun control--United States.
Harvard subject headings:
Criminal records--United States.
Firearms ownership--United States
Firearms--Purchasing--United States.
Gun control--United States
Princeton subject headings:
Criminal records--United States.
Firearms ownership--United States.
Firearms--United States--Purchasing.
Gun control--United States.