In 1994, we passed the Brady Law, putting an end to the days when criminals could "lie and buy" guns from dealers without a background check. The Brady Law requires that every person who wishes to buy a gun from a licensed gun seller undergo a background check to make sure that the buyer is not a criminal or other prohibited person. Brady background checks have been a resounding success.
However, the Brady background check system has a major gap. Because it requires background checks only for gun sales by licensed dealers, criminals can obtain guns with no questions asked from unlicensed sellers, as they are allowed to sell guns without conducting a check in most states. In effect, we have two gun markets: A regulated one, where buyers are checked to see if they can legally buy guns, and an unregulated one, where they are not.
Read the full report No Check. No Gun.