'Terrorist' or 'Mentally Ill': Motivated Biases Rooted in Partisanship Shape Attributions about Violent Actors

We investigated whether motivated reasoning rooted in partisanship affects the attributions individuals make about violent attackers’ underlying motives and group memberships. Study 1 demonstrated that on the day of the Brexit referendum pro-leavers (vs. pro-remainers) attributed an exculpatory (i.e., mental health) versus condemnatory (i.e., terrorism) motive to the killing of a pro-remain politician. Study 2 demonstrated that pro-immigration (vs. anti-immigration) perceivers in Germany ascribed a mental health (vs. terrorism) motive to a suicide attack by a Syrian refugee, predicting lower endorsement of punitiveness against his group (i.e., refugees) as a whole. Study 3 experimentally manipulated target motives, showing that Americans distanced a politically motivated (vs. mentally ill) violent individual from their in-group and assigned him harsher punishment—patterns most pronounced among high-group identifiers.