The
United States Supreme Court, in deciding the case of
Haynes v. United States in favor of the defendant, effectively gutted the National Firearms Act of 1934. As one could possess an NFA firearm and choose not to register it, and not face prosecution due to
Fifth Amendment protections, the Act was unenforceable. To deal with this, Congress rewrote the Act to make registration of existing firearms impossible except by the government (previously, an existing firearm could be registered by any citizen). In addition to fixing the defect identified in
Haynes, the revision tightened definitions of the firearms regulated by the Act, as well as incorporating a new category of firearm, the
Destructive Device, which was first regulated in the
Omnibus Crime Control and Safe Streets Act of 1968. This revision is known as the
National Firearms Act of 1968 to differentiate it from the NFA of 1934, which is a different (and now void) law.