do grant preferences, it is submitted that they do not grant prefer-
ences. That, however, does not arise unless they are held to be
laws in respect of trade, commerce, or revenue. They are not
preferences because (a) s. 99 in referring to laws or regulations of
trade, commerce and revenue means laws or regulations of inter-
State trade or commerce ; and (6) even if that were not so, these
laws are not, upon their true analysis, laws of trade or commerce,
either because (i) their real nature, or pith or substance, is that they
are laws of defence, or (ii) if in their real nature they are not laws of
defence, though they were made under that power, but are laws
dealing with something else then the convenient category is property
and civil rights and not trade or commerce. The real nature, or
pith and substance, for this purpose can be ascertained only upon an
examination of the provisions of the Prices Regulations or the
Rationing Regulations. These regulations are laws of defence, or,
alternatively, they are laws but are not laws of trade or commerce.
The true interpretation of s. 99 is that that section is directed to
limiting the power of the Commonwealth with respect to inter-State
and foreign trade. Section 99, occurring where it does in the
Constitution, is part of the Constitution concerned with inter-State
trade and commerce power. It is not possible to find laws made
by the Parliament under the other legislative heads which are, at
one and the same time, a valid exercise of the legislative powers.
under the other heads and laws of trade and commerce. A law
made, for example, under placitum (v) of s. 51 is really a postal
law and not a law of trade or commerce. In R. v. Barger (1) it was
held, by majority, that the statute there under consideration was
not a proper exercise of the taxation power and that if otherwise
valid, it was invalid on the ground that it authorized discrimination
and therefore discrimination between States or parts of States within
the meaning of s. 51 (ii). Laws regulating trade and commerce are
laws which deal with trade and commerce as such, as complete
concepts, not laws which affect some trade or commercial aspect
(Citizens Insurance Co. of Canada v. Parsons (2) ). Whether it is a
regulation of trade and commerce is to be ascertained by looking at
the pith and substance of the legislation (Attorney-General for Canada
v. Attorney-General for Alberta (3); Attorney-General for Ontario v.
Reciprocal Insurers (4); In re Board of Commerce Act, 1919, and
Combines and Fair Prices Act, 1919 (5); Toronto Electric Com-
missioners v. Snider (6) ). Section 99 presupposes a law made under