15. Vacancy, etc. not to invalidate proceedings of Commission.- No act or proceeding of the Commission shall be invalid merely by reason of— (a) any vacancy in, or any defect in the constitution of, the Commission; or (b) any defect in the appointment of a person acting as a Chairperson or as a Member; or (c) any irregularity in the procedure of the Commission not affecting the merits of the case. | 
