on polite behavior, there were really no attacks at all. in fact, the rolicking obama versus hillary debates we saw at the conclusion didn t happen until february or march of 2008. joe biden might end up seeing a time of old where you weren t expecting the big punches at the first or second debates because it s all about the introduction. we have to leave it there for now. it s going to be a long campaign. margaret, come back soon and mark and jeremy, thank you all. we ll be right back. coming up, five years later the justice department concludes its federal inquiry into the chokehold death of eric garner.