Users of marijuana remain barred from purchasing and possessing guns under a decades-old federal law, even as more and more states move to legalize recreational use of the drug, federal authorities warned this week. Unless marijuana is legalized on a federal level, users of cannabis will continue to be prohibited from shipping, transporting, receiving or possessing firearms and … [Read more...] about Marijuana users still barred from buying guns even in states where pot is legal, ATF warns