A number of countries are investigating the use of neuroactive compounds as a nonlethal way to deal with riots and other domestic crises. The idea is to stun people temporarily, or otherwise change their behaviour, to help the authorities exert control (see page 950).

Russian special forces put that idea into practice in October 2002, when they sprayed a mixture of incapacitating agents into a Moscow theatre in an effort to free some 700 theatre-goers held captive by Chechen rebels. The exact nature of the mixture remains secret; Russian authorities disclosed only that it included a component similar to the opiate fentanyl. But it obviously had a narrow therapeutic window: about 130 hostages died as a result of inhaling the gas.

This episode underscores the ethical conundrum — would the rebels have killed all the hostages? — that makes an outright ban on the military use of incapacitating agents politically unrealistic. Instead, an acrimonious argument over the control of nonlethal weapons is now under way among the states that have signed the Chemical Weapons Convention — which does not cover nonlethal uses for domestic riot control and the like — as well as the Biological and Toxin Weapons Convention, which states that biological agents may be used only for “prophylactic, protective or other peaceful purposes”. Unfortunately, the various sides cannot even agree on how to define the exclusions in the treaties.

During this impasse, the wider community of life scientists should actively discuss the effectiveness and safety of potential incapacitating agents. In particular, academics and non-governmental organizations involved in the debate should agree a list of compounds likely to be considered for use by military agencies, and publish it on the Internet. Scientists could then submit comments to aid its annotation.

Just listing potential agents does not necessarily imply an endorsement of their use. But by providing an accessible forum where scientists can directly engage on the issue of nonlethal weapons, it could help inform the political debate — and might prevent disasters of the sort seen in Moscow.