The words "nor by reason of its having some operation outside the Island" are clear recognition of the continuing existence of the limitation of the powers of a subordinate legislature such as the States of Guernsey. HM Procureur argued that section 2(6) of the 1972 Act governed only English law and does not have any effect as regards the law applicable in Guernsey. In our judgment, this is not correct. Section 2(6) applies by necessary implication to Guernsey. If it did not so apply, it would be open to argument in the Courts of Guernsey that Guernsey local legislation designed validly to implement the EU Treaties so far as concerns Guernsey was void by reason of its extra-territorial effect. It was precisely to prevent any such argument being run that section 2(6) was included in the 1972 Act.

This limitation on the powers of a legislature which is ultimately subordinate to the United Kingdom has been considered in the past solely in relation to legislatures established by statute. For example, there are cases in relation to New Zealand, before by the Statute of Westminster 1931, section 3, it was declared and enacted that "the Parliament of a Dominion has full power to make laws having extra-territorial operation". There are also numerous cases concerning the relationship between the powers of the State legislatures in Australia and those of the Federal Parliament, each being established by legislation with powers expressly defined by such legislation. The principal cases are collected in Halsbury's Laws, Vol. 6 (4th ed. reissue), para. 1028. As the cases make clear, enactments of subordinate legislatures will be held to be valid, even though they have some element of extra-territorial operation, insofar as they are directed to the "peace, order and good government" of the territory: these words come from the Constitution Act of New Zealand considered by the New Zealand Supreme Court in In re Gleich (1879) 1 NZ