1. Unless otherwise provided by law, no public officer or employee whose salary is set by law, whether or not the officer or employee serves the State in more than one capacity, may be paid more than one salary for all services rendered to the State.
2. The provisions of subsection 1 do not apply to any public officer or employee for salaries:
(a) For any ex officio duties the officer or employee may be required by law to perform.
(b) For teaching during off-duty hours in an educational program sponsored by a governmental authority if the officer or employee is not regularly employed in such program by that governmental authority.