why does marco rubio say he's uniquely qualified for the job? we'll bring you his speech live. second-degree manslaughter. new charges again a deputy after another shooting caught on video. he says he thought he was using his stun gun not an actual gun. how did it happen? just shot somebody. we now have a voice recording of officer michael slager soon after he killed a fleeing suspect in south carolina. did he laugh off the incident? and worst of the worst -- which u.s. airline is most likely to arrive late lose your bags or just tick you off? stand by for a new study on the unfriendly case. we want to welcome our viewers from the united states and around the world. i'm wolf blitzer. you're in "the situation room." this is cnn breaking news. and let's get to the breaking news. a new entry in the 2016 presidential race. senator marco rubio is with about to become the third major republican to declare his