Daughter assaulted on city bus. Statement from city bus organization was their driver "failed to act" my daughter is now toi frightened to ride

Your daughter (or you on her behalf, if she is a minor) can sue the bus company, but because it may be owned by a municipality, there may be additional procedural hurdles and time constraints on the suit.  I don't know the exact requirements in Iowa, but you may have only a short time to file a notice of your claim before your suit is barred.  Additionally, there may be statutes which exempt the municpality from liability for negligence, so that you would have to show more than that (i.e. gross negligence or recklessness) to win.  I would recommend that you consult an Iowa attorney as soon as possible.