Misuse of Drugs Act 1971

The Misuse of Drugs Act 1971 (c. 38) is an act of the Parliament of the United Kingdom. It represents action in line with treaty commitments under the Single Convention on Narcotic Drugs, the Convention on Psychotropic Substances, and the United Nations Convention Against Illicit Traffic in Narcotic Drugs and Psychotropic Substances.

Offences under the act include:

The act establishes the Home Secretary as the principal authority in a drug licensing system. Therefore, for example, various opiates are available legally as prescription-only medicines, and cannabis (hemp) may be grown under licence for 'industrial purposes'. The Misuse of Drugs Regulations 2001 (SI 2001/3998), created under the 1971 Act, are about licensing of production, possession and supply of substances classified under the act. These created drug 'schedules', under which the supply of drugs are controlled.

The act creates three classes of controlled substances, A, B, and C, and ranges of penalties for illegal or unlicensed possession and possession with intent to supply are graded differently within each class. The lists of substances within each class can be amended by Order in Council, so the Home Secretary can list new drugs and upgrade, downgrade or delist previously controlled drugs with less of the bureaucracy and delay associated with passing an act through both Houses of Parliament.

Critics of the act such as David Nutt say that its classification is not based on how harmful or addictive the substances are, and that it is unscientific to omit substances like tobacco and alcohol.

These drugs are known in the UK as controlled drug, because this is the term by which the act itself refers to them. In more general terms, however, many of these drugs are also controlled by the Medicines Act 1968, there are many other drugs which are controlled by the Medicines Act but not by the Misuse of Drugs Act, and some other drugs (alcohol, for example) are controlled by other laws.

The act sets out four separate categories: Class A, Class B, Class C and temporary class drugs. Substances may be removed and added to different parts of the schedule by statutory instrument, provided a report of the Advisory Council on the Misuse of Drugs (ACMD) has been commissioned and has reached a conclusion, although the Secretary of State is not bound by the council's findings.

In reality the potential harm has little bearing on the class, which has led to dissatisfaction with drug laws.