varies with the subject-matter of the inquiry. The leading authority is
the decision of this Court in _Re Royal Commission on State Services_
1962 N.Z.L.R. 96.

In recent times Parliament has shown an increasing concern that natural
justice should be observed by Commissions. In 1958 s. 4A was inserted in
the Commissions of Inquiry Act 1908, expressly giving any person
interested in the inquiry, if he satisfied the Commission that he had an
interest apart from any interest in common with the public, a right to
appear and be heard as if he had been cited as a party. Then in 1980,
just as the Erebus Commission was about to start, the section was
replaced and strengthened. The main changes made are that any person who
satisfies the Commission that any evidence given before it may adversely
affect his interests must be given an opportunity to be heard in respect
of the matter to which the evidence relates; and every person entitled
to be heard may appear in person or by his counsel or agent. In giving
this right to representation by counsel the Legislature has gone further
than observations made in this Court in the _State Services_ case at pp.
105, 111 and 117.

Some statements in the judgments in that case are very relevant to the
present case. They are also entirely consistent with the spirit of the
changes made by Parliament in 1980. Gresson P. at p. 105 and North J. at
p. 111 both gave an inquiry into a disaster as an example of the kind of
inquiry where the requirements of natural justice would be more
extensive than in inquiries into a general field. Cleary J. stressed at
p. 117 that, while Commissions have wide powers of regulating their own
procedure, there is the one limitation that persons interested (i.e.
apart from any interest in common with the public) must be afforded a
fair opportunity of presenting their representations, adducing evidence,