♪ ♪ no, i won't back down. ♪ you can stand me up at the gates of hell, but i won't back down ♪ leland: country star jason aldean performing tom petty's "i won't back down" at the start of last night's episode of saturday night live. aldean paying tribute to the late rocker as well as the 358 victims of the -- 58 victims of the las vegas shooting. aldean was performing last sunday when stephen paddock opened fire on that crowd. of course, the shooting sparking a major debate over gun control and the use of after-market devices like bump stocks. it's led to even some of the strongest second amendment advocates to call for an examination. >> we don't believe that bans have ever worked on anything. what we've said has been very clear, that if something transfers a semiautomatic to function like fully automatic, then it ought to be regulated differently. leland: the atf originally