" Their Lordships would...take this opportunity to
point out that in relation to orders of a court of
unlimited jurisdiction it is misleading to seek to draw
distinctions between orders that are 'void' in the
sense that they can be ignored with impunity by those
persons to whom they are addressed, and orders that are
'voidable' and may be enforced unless and until they
are set aside. Dicta that refer to the possibility of
there being such a distinction between orders to which
the descriptions 'void' and 'voidable' respectively
have been applied can be found in the opinions given by
the Judicial Committee of the Privy Council in the
appeals Marsh v. Marsh (1945) AC 271, 284 and MacFoy
v. United Africa Co. Ltd (1962) AC 152, 160; but in
neither of those appeals nor in any other case to which
counsel has been able to refer their Lordships has any
order of a court of unlimited jurisdiction been held to
fall into a category of court orders that can simply be
ignored because they are void ipso facto without there
being any need for proceedings to have them set aside.
The cases that are referred to in these dicta do not
support the proposition that there is any category of
orders of a court of unlimited jurisdiction of this
kind; what they do support is the quite different
proposition that there is a category of orders of such
a court which a person affected by the order is
entitled to apply to have set aside ex debito justitiae
in the exercise of the inherent jurisdiction of the
court without his needing to have recourse to the rules
that deal expressly with proceedings to set aside
orders for irregularity and give to the judge a
discretion as to the order he will make. The judges in
the cases that have drawn the distinction between the
two types of orders have cautiously refrained from
seeking to lay down a comprehensive definition of
defects that bring an order into the category that
attracts ex debito justitiae the right to have it set
aside, save that specifically it includes orders that
have been obtained in breach of rules of natural
justice.
The contrasting legal concepts of voidness and
voidability form part of the English law of contract.
They are inapplicable to orders made by a court of
unlimited jurisdiction in the course of contentious
litigation. Such an order is either irregular or
regular. If it is irregular it can be set aside by the
court that made it upon application to that court; if
it is regular it can only be set aside by an appellate
court upon appeal if there is one to which an appeal
lies."