Sec. 0.5. This chapter does not apply to conduct protected under the Constitution of the United States, the Constitution of the State of Indiana, or a state or federal law or rule, including rights under:
(1) the federal National Labor Relations Act (29 U.S.C. 151 et seq.);
(2) the federal Railway Labor Act (45 U.S.C. 151 et seq.);
(3) IC 22-7; or
(4) a collective bargaining agreement.