Conditions for assigning blame: the impact of necessity and sufficiency

The purpose of the experiment reported here was to examine the impact of necessary and sufficient causal conditions on assignment of blame for a negative outcome. In addition, the influence of inferential goals on the relative impact of necessity and sufficiency was investigated. Subjects read written scenarios in which the pattern of covariation between a target's behaviour and a negative outcome was systematically varied. The results indicate that subjects were able to integrate the covariation data to infer the nature of the causal condition, and utilize this information to infer the extent to which the target was the cause of, and deserving of blame for, a specific negative outcome. There were no effects due to the inferential goal factor. Implications for understanding the impact of necessary and sufficient conditions are discussed.