The average age of youth gang members is about 17 to 18 years (Curry and Decker, 1998), but tends to be older in cities in which gangs have been in existence longer, like Chicago and Los Angeles (Bobrowski, 1988; California Attorney General's Gang Unit, 1996; Klein, 1995; Spergel, 1995). The typical age range is 12 to 24. Although younger members are becoming more common, it is the older membership that has increased the most (Hagedorn, 1988; Moore, 1990; Spergel, 1995). Male gang members outnumber females by a wide margin (Miller, 1992; Moore, 1978), and this span is greater in late adolescence than in early adolescence (Bjerregaard and Smith, 1993; Esbensen and Huizinga, 1993; Moore and Hagedorn, 1996). Gangs vary in size by type of gang. Traditional (large, enduring, territorial) gangs average about 180 members, whereas specialty (e.g., drug trafficking) gangs average only about 25 members (Klein and Maxson, 1996). In large cities, some gangs number in the thousands and even tens of thousands (Block and Block, 1993; Spergel, 1995).
In the early 19th century, youth gangs in the United States were primarily Irish, Jewish, and Italian (Haskins, 1974; Sante, 1991). According to a recent national law enforcement survey, the ethnicity of gang members is 48 percent African-American, 43 percent Hispanic,3 5 percent white, and 4 percent Asian (Curry, 1996). However, student surveys show a much larger representation of white adolescents among gang members. In a survey of nearly 6,000 eighth graders in 11 sites (Esbensen and Osgood, 1997), 31 percent of the students who said they were gang members were African-American, 25 percent were Hispanic, 25 percent were white, 5 percent were Asian, and 15 percent were of other racial and ethnic groups.4 Bursik and Grasmick (1993) point out that, despite the disproportionate representation of minority group members in studies as compared with white youth, "blacks and Hispanics have no special predisposition to gang membership. Rather, they simply are overrepresented in those areas most likely to lead to gang activity."
Miller (1974:220) notes that "observers of any given period tend to relate the characteristics of gangs to those of the particular ethnic groups prominent in the urban lower class during that
Certain offenses are related to different racial/ethnic youth gangs. African-American gangs are relatively more involved in drug offenses; Hispanic gangs, in "turf-related" violence; Asian and white gangs, in property crimes (Block et al., 1996; Spergel, 1990). Numerous ethnographic studies have provided excellent descriptions of Hispanic gangs in Los Angeles. They tend to be structured around age-based cohorts, based in a specific territory (barrio), and characterized by fighting (Moore, Vigil, and Garcia, 1983). The gang provides family-like relationships for adolescents who feel isolated, drifting between their native and adopted cultures and feeling alienated from both (Vigil, 1990a, 1990b; Vigil and Long, 1990). Hispanic gangs have strong links to the neighborhood, or barrio, which tie them to the larger culture (Moore, 1978); much of their violence is related to defense of neighborhood turf. In contrast, African-American gangs in large cities tend to replace traditional social networks that linked youth with legitimate work opportunities (Anderson, 1990). Thus, these gangs tend to be involved in entrepreneurial activities more than other ethnic/racial gangs and may evolve from "scavenger" groups to turf gangs and drug-trafficking gangs (Taylor, 1989).
Use of violence to protect the neighborhood, or gang turf, from rival gangs is also a predominant goal in Chicago (Block and Block, 1993), San Diego (Pennell et al., 1994), and St. Louis (Decker and Van Winkle, 1996). Violence is rarely planned and generally occurs spontaneously among gangs (Decker and Van Winkle, 1996; Sanchez-Jankowski, 1991; Pennell et al., 1994) in response to a wide variety of situations (Horowitz and Schwartz, 1974; Sanders, 1994).
Numerous ways of classifying gangs other than by ethnicity have been devised (Spergel, 1995), although the gangs' complexity, variations, and changing structure practically defy static categories. One way of viewing gangs is along a continuum of degree of organization (Gordon, 1994), from youth groups who hang out together in shopping malls and other places; to criminal groups, small clusters of friends who band together to commit crimes such as fencing operations; to street gangs composed of groups of adolescents and young adults who form a semistructured operation and engage in delinquent and criminal behavior; to adult criminal organizations that engage in criminal activity primarily for economic reasons. The latter, also called criminal gangs, are not considered youth gangs. Distinguishing among these various forms of gangs is often not easy; in some areas, groups may evolve from less formal to more formal organizations along this continuum.
Female Gang Delinquency
Data on the number of female youth gang members have not yet been gathered nationwide; however, several estimates are available. Miller (1992) estimated that approximately 10 percent of gang members were females. Among law enforcement agencies that reported male and female membership data in a 1992 survey, gang membership was estimated to be nearly 6 percent female (Curry, 1995b). In their 11-city survey of eighth graders, Esbensen and Osgood (1997) report that 38 percent of the students who said they were gang members were females. Recent studies of large adolescent samples in urban areas, funded through OJJDP's Program of Research on the Causes and Correlates of Delinquency, report that female membership is higher in early adolescence (Bjerregaard and Smith, 1993; Esbensen and Huizinga, 1993). Among all adolescents, female involvement may be increasing proportionally with male gang involvement (Klein, 1995). Surveys have been incapable of measuring these changes nationwide because data and information systems at the local level are inadequate. Nevertheless, these and other studies of urban samples (Fagan, 1990; Winfree et al., 1992) suggest growing involvement of females in gangs concomitant with gang proliferation.
Are independent female gangs increasing? The initial survey of cities with gang problems indicates that by far the most common female gangs are auxiliary gangs affiliated with male gangs (Miller, 1975). Subsequent surveys suggest an increase in independent female gangs (Curry, Ball, and Decker, 1996; Curry, 1995a, 1995b; National Drug Intelligence Center, 1995). However, Moore (1991:41) suggests that "the general notion that gang girls have moved away
Are female gang members becoming involved in more serious and violent offending? This question cannot be answered definitively because national trend data are not available. Chicago data on gang-related offenses during the 30-year period from 1965 to 1994 show that females represented only 5 percent of victims and 1 percent of offenders (Block et al., 1996). Female gang violence was more likely to involve simple battery or assault rather than homicide, and female nonviolent crimes consisted mainly of liquor law violations.
In the OJJDP-funded Causes and Correlates study site of Denver, Esbensen and Huizinga (1993) found that delinquent behavior was much more prevalent among female gang members than nongang females. However, incidence rates were not significantly higher. In Rochester, another Causes and Correlates study site, Bjerregaard and Smith (1993) also found that female gang members were significantly more likely to engage in serious delinquency than nongang females. However, in contrast to Denver, the incidence rates in Rochester in every offense category were significantly higher among female gang members than among non-gang females. Fagan (1990) also found high levels of involvement in serious delinquency among female gang members in Chicago, Los Angeles, and San Diego. Prevalence rates in all behavior categories, including violent offenses, were higher among female gang members than among nongang males.