:(1) When a police officer is dismissed, removed from service, reduced in rank or salary, except in the following cases, he should be given a reasonable period of opportunity to show reasons for not doing so:
(a) having been convicted of a criminal offense of moral turpitude and sentenced to imprisonment by a court,
(b) on conviction of an offense under this Act and sentenced to imprisonment, or
(c) For showing that it is not possible to give a chance for the vindication, the punishing officer has opened the case and kept the pamphlet.
(2) Only the appointing authority may dismiss, remove from service or reduce the rank or pay of any police officer.