Introduction

Possession is not nine-tenths of the law - it's nine-tenths of the problem.

John Lennon

1.1 DRUG ABUSE

Drugs, whose possession or supply is restricted by law, are known as controlled or scheduled substances. They comprise both licit materials (i.e. those manufactured under licence for therapeutic use) and the illicit products of clandestine factories. Although many plant-based drugs have been self-administered for thousands of years (e.g. coca leaf, cannabis, opium, peyote cactus), the imposition of criminal sanctions is mostly a product of the 20th century. Many of the drugs currently abused were once not only on open sale, but often promoted as beneficial substances by the food and pharmaceutical industries. A pattern developed whereby initial misuse of pharmaceutical products such as morphine, cocaine and amphetamine led to increasing legal restrictions and the consequent rise of an illicit industry. Nowadays, nearly all serious drug abuse involves illicitly-produced substances. Most fall into just a few pharmacological groups, e.g. central nervous system stimulants, narcotic analgesics, hallucinogens (psychotomimetics) and hypnotics. It is still true that the most prevalent drugs are the plant-derived or semi-synthetic substances (e.g. cannabis, cocaine and heroin), but the view of the United Nations Drug Control Programme is that wholly synthetic drugs (e.g. amphetamine, MDMA and related designer drugs) are likely to pose a more significant social problem in the future. According to the World Health Organisation (WHO), scheduled drugs are 'abused' rather than 'misused', but in the following text the two terms are used synonymously. Drugs of abuse may or may not lead to physical or psychological 'dependence': a term used by WHO in preference to 'addiction'.

On the basis of a recent Home Office survey (Drug Misuse Declared in 2000 - see Bibliography), a third of the adult population in the United Kingdom (UK) admits to having used a controlled drug at least once in their lives; fewer than 10% use drugs on a regular basis and for the great majority of these the drug involved is cannabis. The next most common drugs are amphetamine, cocaine and 3,4-methylenedioxymethylamphe-tamine (MDMA). Seizure data from police and customs show a broadly similar pattern. There are currently over 100 000 arrests each year in the UK for drug offences, again the majority involving cannabis. In Europe, it is estimated that 0.2-0.3% of the population are regular heroin users. With few exceptions, the scale of drug abuse has steadily increased in most countries, but it is still predominantly associated with younger members of the population. Mortality from drug abuse has risen rapidly and is largely associated with opiates.

1.2 UK DRUG CONTROL LEGISLATION BEFORE 1971

Apart from the Pharmacy Act of 1868, which restricted the sale of opium, the modern period of drug control started in the early 20th century. Following the Poisons and Pharmacy Act 1908 and the Shanghai Opium Commission in 1909, further restrictions were introduced on cocaine, morphine and opium. More controls on a wider range of substances were introduced by the successive Dangerous Drugs Acts of 1920, 1925, 1951 and 1964. Synthetic amphetamine-like drugs entered the legislation in the Drugs (Prevention of Misuse) Act (DPMA) 1964, and a Modification Order in 1966 added lysergide (LSD) to the DPMA. The Dangerous Drugs Act 1965 consolidated previous legislation.

The first attempts to introduce structure-related generic control into UK drugs law were made with the DPMA of 1964. This contained a statement intended to cover a range of synthetic stimulants. The key feature was a definition of certain side-chain substitution patterns in α-methylphenethylamine (amphetamine) and β-methylphenethylamine. While this did indeed encompass compounds such as phentermine, methylphenidate and diethylpropion, it soon became clear that a refined interpretation of the generic statement unwittingly included dozens of drugs that were not stimulants. In fact, it could be argued that some barbiturates were also covered. This generic control was repealed by a Modification Order in 1970. Following this early failure, it would be some years before generic control of phenethylamines again entered the legislation. But this time (1977), the focus would be on ring-substituted phenethylamines, it would be much more robust and would be followed by generic controls for several other groups.

1.3 THE UNITED NATIONS CONVENTIONS

In international law, controls on drugs of abuse are set out in three United Nations (UN) treaties: The Single Convention on Narcotic Drugs 1961 (UN1961), the Convention on Psychotropic Substances 1971 (UN1971) and The Convention Against Illicit Traffic in Narcotic Drugs and Psychotropic Substances 1988 (UNI988). These treaties are implemented in domestic laws by signatory states, and have been considerably extended in some. In the UK, the corresponding legislation is the Misuse of Drugs Act 1971. Since the inception of the UN conventions, numerous substances have been added to the Schedules, particularly those of the 1971 treaty.

In the 1961 convention, there is a strong emphasis on plant-based drugs (i.e. cannabis, opium and cocaine), with rules for their cultivation, manufacture and trade. In addition, over 100 other substances, mostly synthetic narcotic analgesics, are included, but only a few of these are now used clinically or ever abused. More than 100 psychotropic substances are listed in the 1971 convention, but again only a small fraction is regularly abused. Unlike the treaty of 1961, there is no overarching control of the stereoisomers of psychotropic drugs. Thus in Schedule I, amphetamine, meaning both the (-) and the (+) enantiomers, is listed together with dexamphetamine [the (+) enantiomer of amphetamine] and levamphetamine [the (-) enantiomer] while methamphetamine, meaning the (+) enantiomer, is listed alongside methamphetamine racemate [a mixture of the (-) and (+) enantiomers]. These examples, and the situation whereby the stereochemical configuration of many other substances was left unspecified, has lead to some confusion, but the UN has recently moved to rationalise this matter. These problems have been avoided in the Misuse of Drugs Act by the inclusion of the stereo-isomers of almost all controlled drugs (see Chapter 3).

1.4 PRINCIPLES OF CURRENT UK LEGISLATION

The Misuse of Drugs Act 1971 replaced The Dangerous Drugs Act 1965 and the DPMA 1964 and introduced the concept of 'controlled drugs'. These are defined as those substances or products set out in Schedule 2. The Misuse of Drugs Act, which came into effect in 1973, set up an 'Advisory Council on the Misuse of Drugs' whose terms of reference include a statement of what might...