Possession of narcotics is of course illegal in many jurisdictions. Recently there has been talk of relaxing or eliminating prohibitions on the sale and possession of drugs.
Are there any international treaties or supranational legislation that would be breached if, say, the United Kingdom legalised narcotics? If so, which countries are similarly bound?
Yes, there are international treaties that the UK would breach if they legalised narcotics. Those are:
The Single Convention on Narcotic Drugs, 1961
The Convention on Psychotropic Substances, 1971, and
The majority of UN members are bound by these treaties: 185 of 193 for the 1961 and 1971 treaties, and 189 of 193 for the 1988 treaty. For a full list of signatories and of parties to the treaties, click 'Status of Treaty Adherence' under each treaty.
As to what specific breach the UK would commit if narcotics were legalised, the answer can be found in one of the articles of the 1961 convention:
Article 4. General obligations
The parties shall take such legislative and administrative measures as may be necessary:
(a) To give effect to and carry out the provisions of this Convention within their own territories;
(b) To co-operate with other States in the execution of the provisions of this Convention; and
(c) Subject to the provisions of this Convention, to limit exclusively to medical and scientific purposes the production, manufacture, export, import, distribution of, trade in, use and possession of drugs.
In other words, we are bound by this treaty to enact legislation to ensure that the use and possession of drugs is limited only to medical and scientific use.
For further information about how countries go about managing their international obligations whilst relaxing domestic legislation, the recent example of coca leaf in Bolivia is interesting. After proposing an amendment to the UN Convention against Illicit Traffic in Narcotic Drugs and Psychotropic Substances of 1988 (which was rejected), the country withdrew from and then re-acceded to the Single Convention on Narcotic Drugs, 1961, adding a reservation that exempted coca leaf from the application of the treaty. Some countries objected but not enough to block the country's re-accession.
According to the Global Commission on Drug Policy:
“The idea that the international drug control system is immutable, and that any amendment — however reasonable or slight — is a threat to the integrity of the entire system, is short-sighted.”
