* Barrister, Essex Court Chambers, London.

1. See Government of India v Taylor [1955] AC 491, 503, per Viscount Simonds: “I was greatly surprised to hear it suggested that the courts of this country would and should entertain a suit by a foreign State to recover a tax. For at any time since I have had any acquaintance with the law I should have said, as Rowlatt J said in King of the Hellenes v Brostron (1923) 16 Ll L Rep 190, 193: ‘It is perfectly elementary that a foreign government cannot come here—nor will the courts of other countries allow our Government to go there—and sue a person found in that jurisdiction for taxes levied and which he is declared to be liable to in the country to which he belongs.’ That was in 1923. In 1928 Tomlin J in In re Visser, Queen of Holland v Drukker [1928] Ch 877, 884 … added: ‘… there is a well-recognised rule, which has been enforced for at least 200 years or thereabouts, under which these courts will not collect the taxes of foreign States for the benefit of the sovereigns of those foreign States; and this is one of those actions which these courts will not entertain’.” Viscount Simonds went on (at 508): “there is a rule of the common law that our courts will not regard the revenue laws of other countries: it is sometimes, not happily perhaps, called a rule of private international law: it is at least a rule which is enforced with the knowledge that in foreign countries the same rule is observed. and since it is a rule which operates equally in regard to natural and artificial persons.” See also Brownlie’s Principles of Public International Law, 8th edn (OUP, Oxford, 2012), 479: “The governing principle of enforcement jurisdiction is that a state cannot take measures on the territory of another state by way of enforcement of its laws without the consent of the latter. Persons may not be arrested, a summons may not be served, police or tax investigations may not be mounted, orders for production of documents may not be executed, on the territory of another state, except under the terms of a treaty or other consent given.”