i. Parties to the international drug control treaties are bound to implement their obligations arising from those treaties in full respect for their other obligations under international law, including human rights law. Consistent with international law, these obligations ‘shall be interpreted in good faith in accordance with the ordinary meaning to be given in light of the terms of the treaty in their context and in the light of its object and purpose’.[902] Where there appears to be incompatibility, the principles of treaty interpretation emphasise the strong presumption against normative conflict in international law.[903]
ii. States are assumed not to derogate from their previous obligations when they create a new obligation, such as by ratifying a treaty. Where a number of apparently contradictory instruments are simultaneously applicable, international case law and academic opinion endeavour to construe them in such a way as to coordinate their effects and avoid any opposition between them. Two diverging commitments must therefore be harmonised as much as possible so that they produce effects that are fully in accordance with existing law,[904] including human rights law.
iii. Obligations contained within international drug control treaties may not be used as a basis for violating concomitant international human rights obligations. Provisions contained within an international drug control treaty that allow States to ‘adopt more strict or severe measures’ than those provided by the relevant treaty should be interpreted as allowing only for such measures that align with States’ international law obligations, including human rights law.
When incorporating the obligations of the international drug conventions into domestic law and policy, States must ensure that drug control measures are consistent with concurrent obligations within international human rights law. Where real or perceived conflicts arise between the two legal regimes, these must be resolved in a manner that safeguards human rights protections.
Traditionally, the concept of a conflict of norms describes instances in which it is impossible for a State to simultaneously comply with obligations under two or more treaties.905 In cases where there is a presumed or actual conflict of laws, general rules of treaty interpretation are found under articles 31–33 of the Vienna Convention on the Law of Treaties,906 which are seen as providing authoritative guidance in these matters.907 According to the International Law Commission, articles 31 and 32 are generally agreed to reflect customary international law.908
As described by the Study Group on the Fragmentation of International Law, ‘[i]n international law, there is a strong presumption against normative conflict’.909 It follows that in circumstances where two or more treaty obligations are simultaneously engaged, the ‘correct’, or at least most preferable, interpretation is one that seeks consistency with all the relevant obligations, violating none. This is not simply a question of one body of law ‘trumping’ or overriding another. The process of interpretation requires States to balance concomitant legal obligations across multiple regimes. As explained by the European Court of Human Rights:
Where a number of apparently contradictory instruments are simultaneously applicable, international case-law and academic opinion endeavour to construe them in such a way as to coordinate their effects and avoid any opposition between them. Two diverging commitments must therefore be harmonised as far as possible so that they produce effects that are fully in accordance with existing law.910
For this reason, drug control obligations must never be used to justify laws or policies that violate human rights, as the appropriate implementation of the drug control norm at the national level must take account of human rights standards. The death penalty for drug offences provides a useful illustration of this principle. Executing people for drug-related offences is a clear violation of international human rights law. However, it has been suggested that the international drug control treaties create the option for States to implement capital punishment for drug-related offences,911 in effect overriding or negating human rights obligations.
Capital punishment is not mentioned in the drug conventions. Whether or not a State believes that the absence of comment on this question makes the death penalty a permissible sanction under international drug control law, there is clearly nothing in drug treaties obligating States to adopt capital drug laws. In other words, legislating for capital punishment for drug offences is not required by international drug control law, while executing people for drug offences is prohibited by international human rights law. Therefore, the only option in domestic law consistent with both legal regimes, violating neither, is one that does not allow the death penalty for drug offences. This approach is consistent with that of the International Law Commission, which concludes that ‘[i]t is a generally accepted principle that when several norms bear on a single issue they should, to the extent possible, be interpreted so as to give rise to a single set of compatible obligations’.912
Vienna Convention on the Law of Treaties, 1155 UNTS 331 (1980), art. 31(1).
International Law Commission, Fragmentation of International Law: Difficulties Arising from the Diversification and Expansion of International Law, UN Doc. A/CN.4/L.682 (2006), para. 37; International Court of Justice, Case concerning the Right of Passage over Indian Territory (Portugal v. India), Preliminary Objections, 26 November 1957, p. 142.
European Court of Human Rights, Nada v. Switzerland, Application No. 10593/08, 12 September 2012, para. 170.
C. Wilfred Jenks, ‘The Conflict of Law-Making Treaties’, British Yearbook of International Law, vol. 30 (1953), p. 426.
Vienna Convention on the Law of Treaties, 1155 UNTS 331 (1980), arts. 31–33.
See, e.g., European Court of Human Rights, Golder v. United Kingdom, Application No. 4451/70, 21 February 1975, paras. 29–30; European Court of Human Rights, Witold Litwa v. Poland, Application No. 26629/95, 4 April 2000, paras. 57–64; Johnston and Others v. Ireland (1986) Series A No. 112, para. 51; Lithgow and Others v. the United Kingdom (1986) Series A No. 102, paras. 47–48.
International Law Commission, Fragmentation of International Law: Difficulties Arising from the Diversification and Expansion of International Law, UN Doc. A/CN.4/L.682 (2006), para. 427.
International Law Commission, Fragmentation of International Law: Difficulties Arising from the Diversification and Expansion of International Law, UN Doc. A/CN.4/L.682 (2006), para. 37.
European Court of Human Rights, Nada v. Switzerland, Application No. 10593/08, 12 September 2012, para. 170.
See, e.g., Edith Yunita Sianturi, Rani Andriani (Melisa Aprilia), Myuran Sukumaran, Andrew Chan, Scott Anthony Rush, Indonesian Constitutional Court, [2007] 2-3/PUU-V/2007 IDCC 16; Indian Harm Reduction Network v. Union of India and Ors, Supreme Court of India, Special Leave Petition (Criminal) No 114 of 2012, ‘Affidavit in Reply on behalf of Respondent No. 1&2’, 11 November 2013, para. 4(v).
International Law Commission, Conclusions of the Work of the Study Group on the Fragmentation of International Law: Difficulties Arising from the Diversification and Expansion of International Law (2006), para. 4.