Psychopaths make immoral decisions because they lack emotion when faced with a potentially harmful situation, according to a study recently published in the British Journal of Psychology.

There is plenty of evidence to suggest that emotional processing is linked to moral development and moral judgement. This concept is especially important in the study of psychopathy. Key characteristics of psychopathy include emotional detachment and a tendency to conduct immoral behaviour. Psychopathy is not a clear-cut feature of personality, it is a trait that is found in many people throughout the population to varying degrees.

A prominent theory of morality states that moral deficits in psychopathy are a result of their emotional detachment to distress. As children, we learn to discriminate between good and bad from other people’s emotional responses which reinforce or punish our behaviour. For example, if a child steals his friends toy, and his friend cries, the crying will provoke a negative emotional reaction in the former.

High trait psychopathy individuals (HTP) do not experience a negative emotional reaction to others suffering, so they do not learn to avoid committing immoral acts. Until now research has focused on moral dilemmas that present life or death situations to participants. This doesn’t represent the moral decisions we make on a daily basis.

The study, led by Carolina Pletti (University of Padova, Italy) investigated how psychopathy influences moral decision making in sacrificial dilemmas and every day moral decision making, including situations that both do and don’t result in harm to others. A total of 51 participants who scored either high or low for trait psychopathy completed the experiment.

The results showed that in life or death dilemmas HTP individuals were more likely to sacrifice a person regardless of the consequence. There was no difference between the two groups regarding whether the dilemmas were morally acceptable, suggesting that HTP and low trait psychopathy (LTP) individuals have different underlying mechanisms that influence moral decisions.

There is a division between the two groups in the moral judgement and the decision of whether to commit an immoral act regardless. This suggests that decision is closely linked to emotional processing. In everyday moral decision making LTP individuals were more likely to commit an immoral act in situations that were harmless to others, compared to those that would cause others harm. HTP individuals displayed no difference between these two situations. Overall, the study suggests that moral decision making closely depends on an individual’s emotional processing.