In the year and a half since 20 children were killed by a gunman at Sandy Hook Elementary School in Newtown, Conn., a handful of states have passed laws requiring universal background checks, bans on semi-automatic weapons and limits on high-capacity magazines. But the U.S. remains a patchwork of uneven regulations on firearms, ammunition and gun owners. Meanwhile, at least 44 school shootings have occurred since the Newtown tragedy. If state leaders want to curb... (GunPolicy.org)