Dynamic risk assessment - should you be more wary of a heavier man? 

We know that we should not make judgements about people by their appearance alone and while staff need to be aware of pre-disposing factors, those who are effective in managing violence also avoid jumping to judgements.   

Dynamic risk assessment is a crucial factor in helping staff stay safe. It is a method of enabling them to focus on the key behaviours and risks in a situation in order to decide on their response, rather than making snap reactive decisions based only on the appearance of a person.  Even before dynamic risk assessment is required, there are many primary prevention strategies that can be put in place, such as allowing personal space, leaving exit routes and non verbal communication signals indicating non aggression.

Alcohol and aggression -  The research

However, some reseach does bear out the fact that deep rooted generalisations based on appearance can be valid in making decisions about how to react to a person in a situation.

Research (DeWall et al, 2010) suggests that heavier men are more likely to be aggressive when drunk than lighter men. DeWall and colleagues gave subjects either an alcoholic drink or a placebo drink and asked them to take part in a reaction time competition against a partner. If they won, they were able to inflict an electric shock on their partner. Their partner was fictitious (and the game was fixed so that each subject won 50% of the ties) and aggression was measured by the subject’s decision on how strong the shock should be, and how long it should be given for.

Heavier men who had had an alcoholic drink were more aggressive than those who had had a placebo drink. But having an alcoholic drink made little difference to the behaviour of the lighter men.

The researchers explain this through two models. Evolutionary theory suggests that bigger men should be more prone to aggression, because they are able to inflict greater damage than lighter men, for whom the risks of aggression are potentially greater. This pattern of behaviour has been found in other evolutionary research (Sell et al, 2009; Archer & Thanzami, 2009), but this research goes further, by highlighting the effect of alcohol on the behaviour of heavier men.


John Archer & Vanial Thanzami (2009) The relation between mate   value, entitlement, physical aggression, size and strength among a sample of   young Indian men Evolution and Human Behaviour 30 (5) 315-321

Aaron Sell, John Tooby, and Leda Cosmides (2009) Formidability and the   logic of human anger Proceedings of the National Academy of Sciences 106 (35)   15073–15078

C. Nathan DeWall, Brad J. Bushman, Peter R. Giancola and Gregory D.   Webster (20100 The big, the bad, and the boozed-up: Weight moderates the   effect of alcohol on aggression Journal of Experimental Social Psychology 46   (4) 619-623

Posted by Maybo on July 9, 2012



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