No question in any examination or proceeding by or under the Commission
or examiners shall call for the expression or disclosure of any
political or religious opinion or affiliation, and if such opinion of
affiliation be known no discrimination shall be made by reason thereof
by the examiners, the Commission, or the appointing power. The
Commission and its examiners shall discountenance all disclosure before
either of them of such opinion by or concerning any applicant for
examination or by or concerning anyone whose name is on any register
awaiting appointment.