Commissioners are empowered to exercise some of the ministerial functions of justices. They may witness signatures to documents and take statutory declarations but they are not authorised to administer, take or receive an oath, affidavit or affirmation or receive a complaint or issue a summons or a warrant.
The Minister may appoint persons to be commissioners for declarations. A person may also be a commissioner for declarations if that person is
(a) is authorised to practice as a member of a profession;
(b) a person listed in an employment group; or
(c) a member of a group of persons declared by the Minister to be an occupational group.
Follow this link for a complete list of people who are Commissioners for Declarations because of their professions and employment groups.