The present study focused on the effect of visual presentation on Guilty knowledge test. Twenty-four subjects were chosen to commit a mock crime. After an interval of 7 to 85 days, they were questioned acoustically or by using short video clips which included one critical and five noncritical items. All subjects were offered a monetary reward, if they could not be detected by polygraph. Two series of questions were repeated three times in random order. Skin Resistance Response (SRR), respiration velocity (RV) and heart rate (HR) were recorded. On these indices the main effect of questions between critical and noncritical items was significant in oral-visual presentation. The introduction of a video clip induced a reduction of RV and decreased HR during the critical item while there were no differences for SRR in either group. These results, together with those obtained in previous findings, suggests that aversiveness of the critical item inhibited RV or decreased HR whereas the significance of the stimuli was associated to SRR.

The purpose of the present study was to examine what the Japanese citizens perceived as the causes of juvenile delinquency. Questionnaire was mailed to 1,000 people who were randomly selected from the residents in Sendai, and obtained 345 respondents (191 females and 152 males). 64 items were rated to measure the possible causes of delinquency in the five domains (personality, family, school, community, and society). Factor analysis conducted in each domain established 21 dimensions as a total. Although the respondents perceived diverse causes across the domains, they attributed delinquency especially to the problems involved in personality, family, and society. Further, the older respondents perceived the causes in the personality, family, school, and society domains more serious than the younger ones, and the male respondents perceived family problems more serious than the female ones. Respondents' perception of causes of delinquency may reflect recent trends in delinquency, and also may be affected by the mass media.

In this study, participants (623 students) were examined using two scenarios whether justifiability evaluation of anger expression would be affected by the differences in victim's position or perpetrator's position, the magnitude of damage, and perpetrator's responsibility. As a result, against the prediction, perpetrators tended to evaluate victim's anger expression as being more justifiable than victims. However, since the magnitude of damage and responsibility had significant influences on justifiability evaluation, and these influences were stronger in perpetrators than in victims, the other hypotheses were supported. Moreover, in the specific situation, it was suggested that expressing anger was evaluated as being more justifiable than suppressing anger.

Factors which influence the reconviction after release from medical prison were investigated, including psychiatric factors, demographics, criminal career, type of crime, behavioural problems, etc. Subjects were 145 people who were released from medical prison. After release these subjects were followed during a period of 2 to 7 years. By using Relative Risk Trees for Censored Survival Data Cox Regression, the following nine risk factors were revealed to be significant predictors of reconviction, age of first offence (less than 25.5 years), the lack of need for treatment in special seclusion room, the individual's experience within a criminal institution, anxiolytics medication, maintaining insight, verbal threat perpetuated by individual while in prison, previous illegal drug offenses (volatile substance), age of current offence (exceeds 29.5 years of age), and offences committed in the period of a suspended sentence. This type of research has scarcely been done in Japan until now, the results of this research will be useful to select the candidate for the inmate reeducation program.