Got dui, have not had hearing, police called employer today, I was immediately fired & escorted off the premises, is this legal

Well, it wold seem to me that unless there is a term of employment that prohibits a person from being accused of a crime, that this action was unwarranted. Some federal employees have security clearances that may be jeopardized by an allegation of having committed a crime while intoxicated because such persons might pose a national security risk. Even so, I have not heard of a person terminated without some kind of administrative process that ensures they were not unjustly accused of the crime.