The airline can refuse to let anyone board allowing them flexibility in running their service .. when they're boarded they rightly have to have a valid reason for deboarding someone as set out in the federal rules ..they broke those rules and felt they could abuse the us Marshall support to enforce removing a wholly innocent passenger ... come on guys there is a distinction here ... when u kick someone off a plane you rightly need a valid reason .. not our staff turned up late and decided they want this flight