Moral reasoning theory and illegal behaviour by adults with intellectual disabilities

Many studies conclude there is a strong relationship between moral reasoning and illegal behaviour amongst young offenders. However, there has been no research examining this relationship amongst people with intellectual disabilities. There is some empirical evidence to suggest that the relationship between moral reasoning and illegal behaviour may be curvilinear, such that lower moral reasoning and higher moral reasoning relates to lower rates of illegal behaviour and inappropriate conduct. Given this, and evidence that people with intellectual disabilities are reasoning at a lower moral stage than their same-age peers, it is proposed that some people with intellectual disabilities may actually be less likely to engage in illegal behaviour because they are reasoning at an earlier moral stage, while those with ‘borderline’ intelligence would be more likely to engage in illegal behaviour. This suggests that the relationship between moral reasoning and illegal behaviour is moderated by intelligence, and this has implications for the design of intervention programmes for people with intellectual disabilities, but further research is needed.