of course the nfl is larger but percentage wise you still have to give it to the NFL.
not a week can go by without one of them getting arrested.
but if you want to call BB a sport then the NFL and IFBB lead the way when it comes to murderers. i can think of at least two IFBB killers, bertil fox and titus. the nfl has at least aaron hernandez, OJ and Jovan Belcher.
that's just off the top, there are likely more.