How do Klein and Maxson describe the nature of the gang crime nexus?
In chapter 2 of Street Gang Patterns (Oxford University Press, 2010), Klein and Maxson report statistics on gang arrest profiles in 1994. Their evidence suggests that the relationship between gang membership and crime is "robust across different measures of offending" (page 73). The authors used both self-report measures and crime statistics and found that gang members are more likely to be arrested and to be arrested several times. Therefore, the nexus between gangs and crimes is strong.
The authors also cite research by Thornberry (1998), who looked at longitudinal samples of delinquency in Rochester, Seattle, and Denver. This research found that gang members commit crimes, particularly serious crimes, to a disproportionate degree in every category in every city studied. For example, gang members committed 85% of all robberies carried out by youth in Seattle, 79% of all serious violent crimes, and 87% of all drug sales in Denver (page 73). In Rochester, gang members carried out 86% of all serious violent crimes and 70% of drug sales. In addition, the authors cite research that suggests that gang members are also more likely to engage in non-violent crimes (page 73).
The authors describe the nexus between gangs and crimes as "a cafeteria of delinquency" (page 74), meaning that gang members' offenses fall into every category (similar to the way in which cafeterias serve all varieties of food). This pattern also holds true for gang members of different genders and from different races/ethnicities. While girls in gangs have lower crime rates than boys in gangs, female gang members have higher rates of delinquency than non-gang males, according to many studies. Therefore, the nexus between gangs and crimes is strong across genders and races/ethnicities.