P. D. Phillips (with him T. M. Smith), for the plaintiffs. Legis-
lation of the Commonwealth Parliament should be read, if possible,
so as not to involve the breach of a recognized rule of public inter-
national law. More particularly, a statute authorizing the making
of a subordinate rule having the force of law should not be deemed
to authorize the making of a rule involving a breach of a rule of
public international law (Maawell on the Interpretation of Statutes,
8th ed. (1937), p. 130; Bloxam v. Favre (1); Craies on Statute Law,
4th ed. (1936), pp. 386, 393 ; Oppenheim, International Law, 5th ed.
(1937), vol. 1., p. 40; Jumbunna Coal Mine, No Liability v. Victorian
Coal Miners' Association (2), per O'Connor J.; Niboyet v. Niboyet
(3); In re Ralston; Perpetual Executors and Trustees Association
v. Ralston (4); "Le Louis" (5), per Sir William Scott; R. v. Keyn
(6); The "Annapolis" (7), per Dr. Lushington ; Colquhoun v.
Brooks (8); Mortensen v. Peters (9); Murray v. Charming Betsy
(10), per Marshall C.J.; Potter, Relative Authority of Inter-
national Law and National Law in the United States, (1925) 19
Am. J. IL. 315). Section 13a of the National Security Act must be
subject to implied limitations not to be derived from the mere literal
construction of the words thereof. Some limitation has to be
placed on " persons " in the section. It is not conceivable that the
legislature meant all persons everywhere, so that the subject matter
of the legislation is not such as to justify an application of its literal
meaning. It is not like Mortensen v. Peters (9), because, on any
view, limitations have to be read into s. 13a. These limitations
come from accepted rules of comity and international law. The
tules of international law may be established by reference to the
accepted text writers, the diplomatic practice and policy of the British
Crown, and to right, reason and equity. It is a recognized rule of
public international law, accepted by the British Crown, that the
laws of one sovereign State may not impose the duties of military
service in time of war upon the nationals of other States, except
with the consent of those other states (Oppenheim, International Law,
5th ed. (1937), vol. 1., pp. 237, 540; Walker, Manual of Public
International Law (1895), p. 46; Holland, Lectures on International
Law (1933), p. 149; Halleck's International Law, 3rd ed. (1893),
vol. 1., p. 558; Pitt Cobbett, Cases on International Law, 5th ed.
(1931), vol. 1., p. 202).