In all criminal prosecutions the accused shall enjoy the right to a speedy and public trial by an impartial jury of the county in which the crime shall have been committed; provided that the venue may be changed to any other county of the judicial district in which the indictment is found, upon the application of the accused, in such a manner as now is, or may be, prescribed by law; and to be informed of the nature and cause of the accusation against him, and to have a copy thereof; and to be confronted with the witnesses against him; to have compulsory process for obtaining witnesses in his favor, and to be heard by himself and his council.