Lay person (Juror and citizen judge) have been assumed to decide emotionally rather than rationally, especially in the face of the victim's statements. The previous study, though, does not have support fort this assumption: juror decision making is not always influenced by victim's statements. This study examined the individual sentencing process in a mock trial situation that both Japanese citizen judge system and victim participation system were applied. In particular, the sentencing decision process was examined in terms of vision of the judiciary with a high regard for rational nature. Study1 that 95 undergraduate students participated in revealed that the view of criminal trial which lay weight on rational nature led to lenient sentencing to the defendant. Study 2 (N = 390) shows that the sentencing process noted above result from the motivation to be a "rational judge". Namely, so-called "emotional non-professional" lay person have values of rational nature-oriented to the criminal trial, and they are motivated to decide rationally not emotionally as they confront victim's statements, resulting make the lenient sentencing contrary to the victim's plea. Suggestions for unconformity of previous research and social implications were discussed.
