Although all information given to jurors is identical, the predisposition to make a cognitive effort (need for cognition: NFC; Cacioppo & Petty, 1982) generates differences in decision-making. Thus, jurors low in NFC would tend to consider evidence less thoroughly than those high in NFC. Also, the former individuals may be influenced by emotion-laden information more often than the latter. However, when accountability as an external motive is imposed, low NFC jurors might deliberate information more carefully, and differences in the degree of consideration between those high and low in NFC could be reduced. The present study investigated the effects of accountability and NFC on verdict decisions. The manipulation of accountability was achieved by requesting participants to explain their decision in front of a video camera. The results demonstrated that differences in verdict decisions between those high and low in NFC were not found when jurors were held accountable, while differences were apparent when they were not held accountable. Comparable results were found when assessing anger arousal as a consequence of reading the trial transcript which included emotional evidence. Finally, the function of internal and external motives for juror’s thinking and the impact upon their decision-making is discussed.

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