In Chapter 3, Section 2 , we have provided an outline of the recent rapid rise in juveniles who committed robbery (hereinafter referred to as "juvenile robbery offenders" in this Chapter) and brief descriptions of social background of those juveniles. In order to conduct closer analysis of subjective factors such as juveniles' mental processes leading to the commitment of the offense as well as their personal environment including the relationship with family and friends, thereby revealing the actual circumstances and problems of juvenile robbery offenders, we conducted a special survey at juvenile classification homes throughout Japan.
  The survey was conducted based on records stored in juvenile classification homes targeting: (i) male juveniles involved in robbery cases who were admitted to juvenile classification homes on January 1, 2002, or thereafter and then discharged on the completion of the term of protective detention in 2002 (hereinafter referred to as the "target juveniles of 2002" in this Chapter); and (ii) male juveniles involved in robbery cases who were admitted to juvenile classification homes in 1993 and then discharged on the completion of the term of protective detention (hereinafter referred to as the "target juveniles of 1995" in this Chapter). The number of target juveniles of 2002 was 947 and that of target juveniles of 1993 was 327.
  According to the results of this special survey, this Chapter will conduct analysis of the target juveniles of 2002 focusing on the following points: (i) "increase in the number of perpetrators per case and escalation of violence in robbery cases," in light of the high accomplice rate (rate of the number of cases involving 2 or more perpetrators to the total number of cleared cases) for robbery cases committed by juveniles; (ii) "motives/concepts of modus operandi," with the aim of identifying the reasons that juveniles went as far as to commit robbery; (iii) "personal relationship and environment," from the perspective of examining the relationship with families and society surrounding juvenile robbery offenders; (iv) "characteristics of predispositions," which have been identified in the classification of predisposition. Among others, with respect to motives/concepts of modus operandi, a comparison was made between the target juveniles of 2002 and the target juveniles of 1993 for the purpose of clarifying some of the causes of the recent increase in robbery cases, thereby revealing the recent circumstances and issues of juvenile robbery offenders.