These are interesting times for drug law reform, which, as it gathers pace, is asking important questions of international law. A UN General Assembly Special Session on Drugs is set for 2016 just as national reforms are challenging international treaties that form the bedrock of a global prohibition regime that has dominated since the turn of the twentieth century. States parties to the three UN drug control conventions must now confront the legal and political dilemmas this creates. This is the situation in which the US now finds itself following cannabis reforms in various states that are at odds with these treaties.

The State Department has issued its official position in this regard, one that stretches and boundaries of interpretation and raises other serious questions for international law. In an October statement Ambassador William Brownfield set out thatposition in the form of the ‘four pillar’ approach the United Stateswill now follow in matters of international drug control. While the fourpillars, set out below, have prompted much discussion and debate amongthose working on drug policy issues, attention among international lawyers has been rare. This is something of an important gap given the implications of what the US suggests:

1. Respect the integrity of the existing UN drug control conventions.
2. Accept flexible interpretation of those conventions.
3. Tolerate different national drug policies…[and] accept the fact that some countries will have very strict drug approaches; other countries will legalise entire categories of drugs.
4. Combat and resist criminal organisations, rather than punishing individual drug users

Internationally, the four pillars have emerged in the context of efforts, led primarily by Latin American States, to open discussions on the future of the international drug control regime, and look at alternatives to the current and destructive prohibitionist paradigm. Domestically, it comes in the context of successful referenda to legally regulate cannabis in several US states.

Both of these are welcome developments. The international drug regime is long overdue for reform, and the cannabis referenda will produce many positive criminal justice, health and social outcomes in those US states adopting them. However, domestic cannabis law reform places the United States in a compromised position within the coming debates on the future shape of the international drug control regime.

By permitting legal markets in recreational cannabis, the United States is in breach of both the 1961 Single Convention on Narcotic Drugs and the 1988 Convention on Illicit Traffic in Narcotic Drugs and Psychotropic Substances. This is an awkward position for the US, which for over 100 years has been both the driving force behind the international drug control regime, as well the regime’s de facto policeman. Admitting the breach threatens both a system the US wishes to protect, as well as its own influential role within it. Rectifying the breach domestically requires trampling on State-level democratic ballot initiatives. To its credit the Obama Administration has said via a memorandum from Deputy Attorney General James Cole it will respect and not interfere with the outcomes of those referenda.

The four pillars are a response to this legal and diplomatic conundrum. To justify its contention of treaty ‘flexibility’ – allowing, for example, its legal cannabis market – the US engages in some interesting, if problematic, legal gymnastics. As explained in an earlier speech of Brownfield’s in March:

[I]f it is a living document and they are living documents [the UN drug control conventions], living means you are allowed to adjust your interpretation as the world changes around you, the world in 1961 was a different place from the world in 2014 and we the governments and members states of the UN system should be permitted to interpret with that degree of flexibility as we move in to the 21st century.

Using the language of treaties as living documents – more commonly known as dynamic or evolutive interpretation – Brownfield attempts to paint cannabis legalisation in the US as something other than the breach it obviously is, in the process raising a number of international legal concerns.

Dynamic interpretation is well established in international human rights law, particularly the jurisprudence of the European Court of Human Rights. But, as described by the International Law Commission in 2006, it is an approach ‘much more deeply embedded in human rights law than in general international law’, suggesting that its application in the context of international drug control law must be considered cautiously. This is not to suggest that dynamic interpretation is not evident in other regimes, and it indeed has been used by the International Court of Justice, the European Court of Justice and the Appellate Body of the World Trade Organization in various cases.

The drug treaties are suppression conventions. They form part of the body of transnational criminal law, not international human rights law. However, we accept that, for a variety of reasons it is legitimate to apply a dynamic interpretive approach to elements of international drug control law, particularly where drug control engages human rights. However, there are clear problems with the US’s use of this approach.

The first is the limits of interpretation itself. The classic approach to dynamic interpretation, as established by the European Court in Tyrer v UK, is a process of broadening or expanding the understanding of an obligation based upon changes in law, evolving social norms or widespread change in State practice. In other words, understanding treaty language in a modern context. There are various examples of this in practice from differing legal regimes.

However, Brownfield suggests that the ‘living’ nature of the drug treaties means that an obligation can legitimately evolve to the point of meaning the exact opposite of what it states, and that somehow the non-medical, non-scientific use of cannabis has evolved from being illegal in international law to being legal. This is an absurdity. The treaties already include a mechanism for the status of individual drugs to change or evolve, and for individual substances can be included in, or removed from, international control with approval of the UN Commission on Narcotic Drugs, a process known as ‘rescheduling’. The Brownfield approach circumvents this, for the obvious reason that such a resolution would never make it through the Commission, and instead posits the ‘living instrument’ idea as the alternative.

However, for this outcome to be legally valid without cannabis being rescheduled, dynamic interpretation would need to alter the understanding of what the term ‘medical and scientific use’ means within the conventions, the only circumstance within the current international regime under which cannabis, and all controlled substances, may be legally manufactured, accessed and used. But Brownfield does not suggest this, for if he did then this evolved understanding of medical and scientific use could reasonably be applied to all drugs under international control, making legal recreational access to all controlled drugs part of the new ‘living’ drug regime. This is clearly a bridge too far for the US.

The second problem is one of interpretive forum. Dynamic interpretation is a judicial approach, utilised by judges or adjudication bodies to balance competing or conflicting interests in arriving at a decision. It is an approach employed by a neutral arbiter to dispute resolution, not a doctrine for States to use to unilaterally change the nature and scope of their own treaty obligations. Indeed, if we are to pursue an evolutive approach, then we also need to look at broader State practice. You can easily count on the fingers one hand the number of countries with a legalised recreational cannabis market, so this approach has clearly not evolved to an extent where legal regulation of the substances within the treaties would be permissible. Even then it is stretching any reasonable interpretation to reverse what the law in fact says. But in any case Brownfield does not suggest that we look to evolving State practice. The four pillars suggest, quite clearly, the acceptance of divergent unilateral interpretations. Whatever one thinks of the drugs treaties, such an approach creates an international minefield. Imagine an international legal order in which individual States are allowed to decide for themselves which treaty obligations apply to them, and in what way.

Here, however, we come to the third major problem, which is that the flexibility the US seeks for itself may not extend to others at all. We have both argued separately that this new US position has little to do with treaty compliance, and is really about maintaining its own central role as global arbiter of drug control, a position which it uses to great influence internationally. Surprisingly, US drug czar Michael Botticelli recently admitted as much in his Senate confirmation hearings, stating that ‘[t]he Four Pillar framework is an effort to stake out a middle ground between those who believe that prosecution and jail is the only approach and those favoring radical changes to the conventions’. In effect, the US denial of its own treaty breach allows it to sit in judgement over the drug reform actions of other States, comfortable in its self appointed role of neutral ‘middle man’ or ‘referee’ of acceptable treaty flexibility, and therefore protecting its own national interests against any ‘radical changes to the conventions’, apart from its own.

To be clear, our concern is not about compliance with bad laws, which these treaties surely are. Our concern is with the potential implications of the State Department’s argumentation. The failed, punitive prohibitionist approach of the international drug control regime must end. It is a regime that causes untold human and societal damage across the globe, and change to this regime is slow yet becoming more inevitable. However, it would be unfortunate to see established rules of international law become collateral damage in the fallout of the end of the war on drugs.

Dr Rick Lines and Damon Barrett are the Chair and Director of the International Centre on Human Rights and Drug Policy, University of Essex.