台灣社會變遷迅速，家庭結構及功能隨之變動，少年的行為受到很深的影響。少年犯罪問題，不論是歐美日本或是國內，皆是受到重視的議題，它不但是學術熱題也是法務實務的重點。我國在面對少年犯罪，有少年事件處理法的少年司法機制因應，在我國已實施近四十年的經驗，並發展出有台灣特色的少年司法制度。正值少年法修訂的當下，若能反思該法的優缺點，將為台灣建構出二十一世紀的新少年法。本研究乃是針對少年首次進入少年司法的調查處遇過程，進行分析研究，以了解其首犯及調審處遇的歷程，期待能夠看出少年進入少年司法後的脈絡變化，以利檢視是否達成健全少年性格的目標。本研究蒐集766位首犯少年在法院裁定的資料，進行首犯年齡的分析，發現他們的首犯年齡平均數為15.10歲。按首犯少年不同犯罪類型的年齡平均數之低高順序排列，則為非暴力犯罪(14.55歲)、虞犯其他(14.89歲)、非性暴力犯罪(15.19歲)、性犯罪(15.35歲)及毒品犯罪(15.96歲)。五種犯罪類型少年進行變異數分析，並且以Bonferroni的事後比較，達到顯著性差異。在經過事後兩兩比較，得到係非性暴力犯罪、非暴力犯罪及毒品犯罪等三種類型少年倆倆首犯年齡平均數變項間皆有顯著差異。非暴力犯罪首犯少年較早就開始犯罪，非性暴力犯罪首犯少年則是排行在中間，毒品犯罪首犯少年則是最晚才開始犯罪。性犯罪首犯少年則是排行較晚倒數第二才開始犯罪。少年首犯不同犯罪類型人數多寡，依序排名為非性暴力犯罪、非暴力犯罪、毒品犯罪、性犯罪及虞犯其他。首犯少年在調查階段就因管轄轉移、不付審理離開法律程序、因微罪不罰採取不付審理轉向處分等的人數案件，就佔有20.4%二成的比例。少年首犯在審理階段，不管在家或不在家，或在家園或在機構的保護處分，佔首犯少年總數的76.9%，將近有七成七之多。調查及審理前後二階段的主流處理，首犯少年的法律處遇人數就將近有九成七之多的數量。首犯少年的法律處遇方式，採取社區處遇模式的比率佔其首犯少年總數的八成五。實證結果支持Farrington's (1989)結論首犯年齡依犯罪類型而有所不同。這對爾後少年犯罪類型特殊化的研究有所幫助。

Rapid social change, along with changes in family structure and function, juvenile behavior is influenced deeply. Juvenile delinquency, both America and Japan or domestic, are the subject of attention, which is not only a hot topic of academic research but also the focus of judicial system. In the face of juvenile delinquency, they cope it with juvenile justice mechanisms in the law of process of juvenile event. Our country has implemented nearly four decades of experience by that law and developed the characteristics of the juvenile justice system in Taiwan. In the moment of juvenile law revision, if we review the advantages and disadvantages of the Act, we will reconstruct a new twenty-first century juvenile law for Taiwan. In this study, we analysis and research the onset of juvenile offending in the juvenile justice , in order to understand the onset of juvenile offending and process of investigation-trial, we expect to see them changing in the context of juvenile justice and examine whether the benefit to sound development of personality . This study collected 766 juvenile delinquents’ data from juvenile court, they was analyzed and found their average age of onset of juvenile offending (15.10 years). According to the average age of the different crime types of onset of juvenile offending ,their low-high order is non-violent crimes (14.55 years), anticipated-offending others (14.89 years), non-sexual violent crimes (15.19 years), sexual offenses (15.35 years) and drugs Crime (15.96 years). Five types of juvenile crime were analysed by one way ANOVA, and Bonferroni post hoc comparison to get a statistical significance. After afterwards pairwise comparison, we obtained a non-sexual violent crime, non-violent crime and drug-related crimes, three types of juvenile delinquency have significant differences every two types each other. Non-violent juvenile delinquent began earlier offending, non-sexual violent juvenile delinquent is ranked in the middle, drug-related juvenile delinquent is the latest offending. Juvenile sex offender is ranked No.2 from the back of later offending. The number of different types of juvenile delinquency sequentially rank, non-sexual violent crimes, non-violent crimes, drug crimes, sex crimes and anticipated-offending others. Juvenile delinquents in the investigation stage of juvenile law, because of the transfer of jurisdiction, leave juvenile justice without pay for the trial proceedings, because micro impunity does not pay to take the trial sanctions such as the number of cases, it holds 20.4% . Juvenile delinquent in the trial stage, whether at home or not at home, or in institutions, the case number of protective treatment, accounting for 76.9 percent of juvenile delinquent of the total, nearly 77% as much. In the law of process of juvenile event, take the case of community treatment at a ratio of 85 per cent of its total number of juvenile delinquent. The empirical results support Farrington's (1989) conclusion that age of onset of offending varied according to the type of crime. This results will help later specialized study of juvenile delinquency.