How effective are background checks? This article at Politico is very telling.
Is this telling us something we already don't know? Hardly. Criminals don't follow laws and restrictions. Such background checks look not to help so much in this regard. When policies are coming from gun control advocates, they're seeking to legitimize any and every restriction and hurdle on the RKBA, because they're trying to achieve their end game.
Researchers in 2000 reviewed more than a decade of crime data in states with and without background checks. They found no significant difference in murder rates in states that had implemented the checks and states that had not, according to the study, which was published in The Journal of the American Medical Association.