Furthermore, there are many factors which can lead to integration within a gang, making it difficult to predict or prevent (Winfree Jr., Fuller, Vigil & Mays, 1992). For many people, time within a gang constitutes an important part of their life, however, a large number also successfully leave a gang (Pyrooz & Decker, 2011). It is important to understand the culture of gangs to help find ways of preventing youths from entering gangs, or helping them to successfully exit.
One important study that has focused on delinquency in adolescents is the Rochester Youth Development Study. This research is critically important, because it considers the behavior of youth, as well as the causes and consequences of this behavior over a long period of time. The research first started in 1986, and followed a sample of 1,000 adolescent juveniles from the 7th and 8th grades in public schools within Rochester New York, through to their early adulthood. In this study, gang membership was present in a third of the sample group, yet it was responsible for 86% of serious acts of delinquency as well as 70% of sales of drugs that occurred within the group. Those who were gang members committed violent offensives more often when they were actively part of the gang than either before joining or after leaving. The authors examined violent behavior taking into account all other potentially confounding factors, including prior violence, and poverty, and still found a significant association between being active in a gang and violence. The authors argued that this result suggested that the norms of behavior within the gang, as well as group dynamics, strongly contributed to the prevalence of violence and delinquency (Thornberry, Krohn, Lizotte & Smith, 1998).
This article focused on examining the behavior of adolescents across time without any selection for gang activity. Because of this, the sample size and the duration of the study, it