The Erebus Commission, like others in the past in New Zealand when a
Supreme Court Judge has been the Chairman or the sole Commissioner, was
expressed to be appointed both under the Letters Patent delegating the
relevant Royal Prerogative to the Governor-General and under the
authority of and subject to the provisions of the Commissions of Inquiry
Act 1908. Some of us have reservations on various legal
questions--whether the Commission had statutory authority for its
inquiry as well as Prerogative authority; whether the findings in the
body of the report amounted to 'decisions', whether complete absence of
evidence is relevant in considering natural justice or can be redressed
in proceedings of this kind. These questions may be of more importance
in cases concerning the Thomas Commission which are to come before this
Court next year. Moreover, though most important in principle, they are
highly technical. It seems to us preferable that the Court should not
determine them now unless it is essential to do so. And we do not think
it is essential, because we are agreed on what now follows and it
enables substantial justice to be done in the present case.

It is established in New Zealand that in appropriate proceedings the
Courts may prevent a Commission of Inquiry--whether a Royal Commission,
a statutory Commission or perhaps a combination of the two--from
exceeding its powers by going outside the proper scope of its inquiry.
That basic principle was clearly accepted by this Court in _Re Royal
Commission on Licensing_ 1945 N.Z.L.R. 665. See especially the judgment
of Myers C.J. at pp. 678 to 680. As he indicated, the principle is
implicit in the judgment of the Privy Council in _Attorney-General for
Commonwealth of Australia v. Colonial Sugar Company_ 1914 A.C. 237. It
is also clear that in a broad sense the principles of natural justice
apply to Commissions of Inquiry, although what those principles require