Section 6. Statements made by persons to the Commission

6. Statements made by persons to the Commission.— No statement made by a person in the course of giving evidence before the Commission shall subject him to, or be used against him in, any civil or criminal proceeding except a prosecution for giving false evidence by such statement: Provided that the statement— (a) is made in reply to a question which he is required by the Commission to answer, or - (b) is relevant to the subject matter of the inquiry.