Alcohol and violence
Marshall (1979) described the cross-cultural study of alcohol as 'a classic natural experiment: a single species (Homo Sapiens), a single drug substance (ethanol) and a great diversity of behavioural outcomes.' The 'natural experiment' of cross-cultural research finds levels of variance in the behavioural consequences of drinking which demonstrate that cultural norms and beliefs about alcohol can modify, direct or even override the physiological and psychological effects of alcohol (Douglas, 1987; McDonald, 1994; Heath, 1995; SIRC, 1999; etc.)
Reviews of ethnographic evidence show that the behavioural outcomes of drinking are always in accord with what people in a given culture (or sub-culture) expect to happen, and that individuals internalise such expectations during the learning process of socialisation (Mandelbaum, 1965; MacAndrew and Edgerton, 1969; Critchlow, 1986; Heath, 1998). Experiments conducted under controlled conditions (double-blind, with placebos) in different cultures confirm that aggressive behaviour is determined by cultural expectations rather than the chemical actions of ethanol: in cultures where alcohol is believed to cause aggression, subjects become aggressive even when they have been given a placebo (Rohsenow and Bachorowski, 1984; Vogel-Sprott, 1992; Neff, 1991; Milgram, 1993). The fact that psychological experiments have generally involved relatively low doses of alcohol (in accordance with professional ethics), has led some reviewers to conclude that cultural expectations only determine behaviour at low blood-alcohol concentrations (e.g. de Vente et al, 1998). This rather simplistic assumption is not supported by the ethnographic evidence, or research conducted in natural settings, which shows behaviour reflecting cultural expectations at all levels of alcohol consumption (MacAndrew and Edgerton, 1969; Marshall, 1983; Levine, 1992; Heath, 1998).