incorporation approach to customary international law and Sir Anthony Mason, in his extra-judicial writings, has noted that in Australia we seem to prefer the transformation approach to customary international law. However, both treaties and customary international law have been used quite frequently by the courts in the development of the common law and in the interpretation of legislation More recently, treaties have been used in the area of legitimate expectations in administrative law. The question that remains is whether and how international law may be used in constitutional cases I. INTERNATIONAL LAW IN CONSTITUTIONAL CASES: 1901-1996 International law has been raised in various constitutional cases over the years in relation to diverse issues, including (a) international law as a limitation on legislative power (b)international law as a source of legislative power (c) the determination of the existence of a sufficient nexus between a State and the subject matter of a State law (d) the interpretation of section 44 of the Constitution 20 14 Anthony Mason, "International Law as a Source of Domestic Law"in Brian Opeskin(ed) International Law and Australian Federalism(1997), 218. And see generally the discussion in bove n 6 See discussion in Walker, above n 6. 209-218: Rosalie Balkin "International Law and domestic Law"in Sam Blay, Ryszard Piotrowicz and Martin Tsamenyi(eds), Public International Law: An Australian Perspective(1997)119, 122, 132-135 16 Minister for immigration and Ethnic Affairs v Teoh(1995)183 CLR 273 Polites v The Commonwealth(1945)70 CLR 60: Horta v The Commonwealth(1994)181 CLR 183 Polyukhovich v The Commonwealth(1991)172 CLR 501 1 Roche v Kronheimer(1921)29 CLR 329: Rv Burgess; Ex parte Henry (1936)55 CLR 608: Rv Poole: Ex parte Henry ([No 2/(1939)61 CLR 634; Airlines of New South Wales Pty Ltd v New South Wales/No 2](1965)113 CLR 54: The Commonwealth Ta (1983)158 CLR 1; Kirmani v Captain Cook Cruises Pty Ltd(1985)158 CLR 351; Gerhardy v Brown(1985)159 CLR 70 Richardson v Forestry Commission(1988)164 CLR 261; Queensland v The Commonwealth(1989) 167 CLR 232(The Queensland Rainforest Case): Victoria v The Commonwealth(1996)187 CLR 416 (The Industrial Relations case) Inion Steamship Co of Australia Pty Ltd v King(1988)166 CLR 1incorporation approach to customary international law and Sir Anthony Mason, in his extra–judicial writings, has noted that in Australia we seem to prefer the transformation approach to customary international law.14 However, both treaties and customary international law have been used quite frequently by the Courts in the development of the common law and in the interpretation of legislation.15 More recently, treaties have been used in the area of legitimate expectations in administrative law.16 The question that remains is whether and how international law may be used in constitutional cases. I. INTERNATIONAL LAW IN CONSTITUTIONAL CASES: 1901–1996 International law has been raised in various constitutional cases over the years in relation to diverse issues, including: (a) international law as a limitation on legislative power;17 (b) international law as a source of legislative power;18 (c) the determination of the existence of a sufficient nexus between a State and the subject matter of a State law;19 (d) the interpretation of section 44 of the Constitution;20 14 Anthony Mason, "International Law as a Source of Domestic Law" in Brian Opeskin (ed), International Law and Australian Federalism (1997) , 218. And see generally the discussion in Mitchell, above n 6. 15 See discussion in Walker, above n 6, 209-218; Rosalie Balkin, "International Law and Domestic Law" in Sam Blay, Ryszard Piotrowicz and Martin Tsamenyi (eds), Public International Law: An Australian Perspective (1997) 119, 122, 132-135 16 Minister for Immigration and Ethnic Affairs v Teoh (1995) 183 CLR 273. 17 Polites v The Commonwealth (1945) 70 CLR 60; Horta v The Commonwealth (1994) 181 CLR 183; Polyukhovich v The Commonwealth (1991) 172 CLR 501. 18 Roche v Kronheimer (1921) 29 CLR 329; R v Burgess; Ex parte Henry (1936) 55 CLR 608; R v Poole; Ex parte Henry ([No 2] (1939) 61 CLR 634; Airlines of New South Wales Pty Ltd v New South Wales [No 2] (1965) 113 CLR 54; The Commonwealth v Tasmania (1983) 158 CLR 1; Kirmani v Captain Cook Cruises Pty Ltd (1985) 158 CLR 351; Gerhardy v Brown (1985) 159 CLR 70; Richardson v Forestry Commission (1988) 164 CLR 261; Queensland v The Commonwealth (1989) 167 CLR 232 (The Queensland Rainforest Case); Victoria v The Commonwealth (1996) 187 CLR 416 (The Industrial Relations case). 19 Union Steamship Co of Australia Pty Ltd v King (1988) 166 CLR 1. 4