In January 1988 Dr Stephen C. Joseph, the New York City Health Commissioner, gained approval from the state health administration for a medical experiment, a controlled clinical trial. Usually the conduct of a clinical trial is respectfully left to experts; rarely will its origins be announced on the front page of the New York Times, with its fortunes chronicled in subsequent editions. But this was no ordinary scientific trial. Law enforcement officials immediately called the experiment ‘unthinkable’, and many of the city's minority leaders denounced it as ‘genocide’. The trial was designed to recruit a limited number of drug addicts to a treatment group permitted to trade-in used needles and syringes for sterile equipment, and to compare their progress with a control group not given the same access to clean paraphernalia. From the beginning, New York's experimental needle exchange scheme, like so many other public health initiatives aimed at controlling HIV infection, was controversial, a focus for fear, frustration and political manoeuvre in the city. The troubled history of the needle exchange scheme illustrates the constraints on health promotion in a liberal American city overwhelmed by AIDS, drug addiction and racial tension.

Although it has recently been argued that the development of AIDS policy offers ‘many examples of the triumph of the ethic of professionalism over the confused and conflicting claims of morality and ideology’, the attempt to establish a needle exchange scheme in New York is not such an instance.