The prisoner's dilemma

OVER the past decade, the number of people jailed for drug offences has trebled to 8,500. As more and more addicts have been imprisoned, drug-taking in prison has greatly increased. Research suggests that as many as one in five prisoners regularly takes illicit drugs. Many more use them occasionally. The Prison Service is trying a variety of counter-measures, including drug-free wings where prisoners who promise not to use drugs are given additional privileges. But stopping drugs being smuggled into prisons is impossible without draconian measures such as banning close-contact family visits.