Youth gang affiliation, violence, and criminal activities: A review of motivational, risk, and protective factors

Aggression and Violent Behavior 18 (2013) 417–425

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Aggression and Violent Behavior

Youth gang affiliation, violence, and criminal activities: A review of motivational, risk, and protective factors Kate O’Brien a,⁎, Michael Daffern a,b, Chi Meng Chu a,c, Stuart D.M. Thomas a,d a

Centre for Forensic Behavioural Science, Monash University, 505 Hoddle Street, Clifton Hill, Melbourne, Victoria 3068, Australia Victorian Institute of Forensic Mental Health, 505 Hoddle Street, Clifton Hill, Melbourne, Victoria 3068, Australia Clinical and Forensic Psychology Branch, Ministry of Social and Family Development, 512 Thomson Road, MSF Building, #12-00, S(298136), Singapore d School of Psychology, University of Wollongong, NSW, 2522, Australia b c

a r t i c l e

i n f o

Article history: Received 18 December 2012 Received in revised form 30 April 2013 Accepted 2 May 2013 Available online 17 May 2013 Keywords: Youth gangs Risk factors Recidivism Violence Juvenile delinquency Desistance

a b s t r a c t Youth gangs are a universal phenomenon attracting increasing attention; the criminal and antisocial behavior perpetuated by youth gangs has an adverse impact on local communities across the globe. Although there is an extensive body of research that has examined the problems posed by youth gangs in America (and more recently in other countries), there have been relatively fewer empirical studies that examined the factors and psychological processes that are related to youth joining and leaving gangs. This review compiles the international research on the nature of youth gangs and critically evaluates: (a) the factors that motivate engagement in and desistance from gang-related activities, (b) risk and protective factors that impact on youths' propensity for gang membership, delinquency, and violent behavior, and the adverse consequences associated with gang affiliation, and (c) the relationship between gang-affiliation, youth violence, and criminal behavior. © 2013 Elsevier Ltd. All rights reserved.

Contents 1. 2. 3. 4.

Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Methodology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Definition of youth gangs . . . . . . . . . . . . . . . . . . . . . . . Global trends in youth gang affiliation . . . . . . . . . . . . . . . . . 4.1. Youth gang characteristics . . . . . . . . . . . . . . . . . . . . 5. Gang membership, violence, and crime . . . . . . . . . . . . . . . . . 5.1. Interpreting the gang–crime relationship . . . . . . . . . . . . . 5.2. Risk factors for gang membership . . . . . . . . . . . . . . . . 5.3. Risk factors for youth violence versus gang membership . . . . . . 5.4. Patterns of risk prediction . . . . . . . . . . . . . . . . . . . . 5.5. Protective factors . . . . . . . . . . . . . . . . . . . . . . . . 6. Motivation for joining and desisting from gangs and persistence processes 7. Consequences of gang membership . . . . . . . . . . . . . . . . . . . 8. Conclusion, limitations and future research . . . . . . . . . . . . . . . References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

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1. Introduction ⁎ Corresponding author at: Centre for Forensic Behavioural Science, Monash University, 505 Hoddle Street, Clifton Hill, Victoria 3068, Australia. Tel.: +61 3 9947 2600; fax: +61 3 9947 2650. E-mail address: [email protected] (K. O’Brien). 1359-1789/$ – see front matter © 2013 Elsevier Ltd. All rights reserved. http://dx.doi.org/10.1016/j.avb.2013.05.001

Youth gangs are a universal phenomenon attracting increasing attention. Although variations in gang activity are observed across settings and contexts, the criminal and antisocial behavior of youth gangs is known to have an adverse impact on local communities

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across the globe. An extensive body of research has examined the problems posed by youth gangs in America, with research beginning to emerge in other countries (Klein, Weerman, & Thornberry, 2006). Specifically, international research has consistently demonstrated that youth gang members contribute disproportionately to the overall level of crime, especially violent and serious offenses (Chu, Daffern, Thomas, & Lim, 2012; Krohn & Thornberry, 2008), and that gang affiliation can significantly disrupt life course transitions (Thornberry, Krohn, Lizotte, Smith, & Tobin, 2003). Importantly, these studies have found similarities, but also important differences, between youth gang offenders and those who are not gang-affiliated. This paper reviews and critically evaluates diverse research on the nature of youth gangs and the factors that motivate engagement in and desistance from gang-related activities, risk and protective factors associated with gang membership, and explores the adverse consequences associated with gang affiliation, including extensive research on the gang– crime relationship. 2. Methodology Searches were conducted in a variety of publication databases, relevant peer-reviewed journals, one mainstream Internet database, and national and international juvenile justice departmental and gang research websites. These included: (a) Ovid PsychINFO and Criminal Justice Abstracts; (b) Juvenile Justice Bulletin (not peer reviewed); and (c) Juvenile justice and gang research websites (e.g., The Eurogang Project, the National Gang Crime Research Center, the Office of Juvenile Justice in the U.S.), and (d) a Google search for unpublished articles available online. Search terms included combinations of: youth gangs, gangs, gang member, troublesome youth group(s), delinquent youth group(s), adolescent, adolescence, juvenile, juvenile justice, youth, young offender, recidivism, risk factors, and desistance. These search terms yielded 672 published texts (articles, books, book chapters, and government reports), which were then sorted for relevance by title and abstract; references meeting the inclusion criteria were then extracted and reviewed. To be included in the review, materials needed to focus specifically on youth gangs or gang members, rather than juvenile delinquency generally, and covered the following areas of research: (a) predictors of youth gang membership and desistance, (b) reasons provided by youth for joining and leaving gangs, and (c) the antisocial and non-criminal consequences of gang membership (including the association between gang membership and criminal behavior). In total, approximately 200 references were reviewed for inclusion in this review. Most articles and reports regarding youth gangs originated in the United States; a number also originated from the United Kingdom, Canada, and Europe. Very few studies to date have focused on the characteristics, development, and formation of Asian youth gangs, although a number of studies have recently emerged from Singapore, China, Korea, and Hong Kong.

five defining characteristics for youth gangs. This definition asserts that, “a street gang is any durable, street-oriented youth group whose involvement in illegal activity is part of its group identity” (Klein & Maxson, 2006, p. 4). Other characteristics (e.g., ethnicity, tattoos, and gang names) are “descriptors” that delineate particular gangs or are elements that describe specific groups, rather than necessary “definers” of youth gangs (Klein & Maxson, 2006; Wood & Alleyne, 2010). Consistent with the Eurogang definition, many definitions of youth gangs have included illegal activity as a defining feature (Klein & Maxson, 2006; Miller, 1975; Thrasher, 1963). However, other researchers have debated the importance of including criminality as a necessary criterion for defining youth gangs (Ball & Curry, 1995; Howell, 1998; Short, 1996). They emphasize the importance of a shared identity, solidarity and identified territory as more critical determinants of youth gangs (Esbensen et al., 2001); and note that most criminality among young people occurs in concert (Chu et al., 2012). Self-nomination (i.e., answering questions such as “Do you belong to a gang?”) has traditionally been considered by many American researchers to be a “particularly robust measure of gang membership, capable of distinguishing gang from non-gang youth” (Esbensen et al., 2001, p. 124), but this is not considered to be a valid indicator of involvement with gangs among European researchers (Gatti, Haymoz, & Schadee, 2011; Sharp, Aldridge, & Medina, 2006). Research suggests that as the definition or scope of gang involvement changes, prevalence estimates of gang membership and the qualities and activities of youth gangs shift (Esbensen et al., 2001; Matsuda et al., 2012; Winfree, Fuller, Vigil, & Mays, 1992). Additional difficulties arise when theoretical definitions compared to self-nomination are utilized as a strategy for identifying gang members. For example, a recent comparison of three definitions of gang membership (i.e., Eurogang, self-nomination, or identifying friends as gang members) resulted in limited definitional overlap, with each conceptualization capturing a unique group of individuals. Importantly, however, each definition captured a subsample of “gang” youth that were distinct from nongang youth; suggesting that there are unique characteristics associated with gang membership, regardless of the definition used to identify gang affiliation (Matsuda et al., 2012). Notwithstanding the differences associated with the conceptualization of youth gangs and continued disagreement about the necessary criteria for gang membership, most definitions include the following characteristics: “(1) a self-formed group united by mutual interests (2) that controls a particular territory, facility or enterprise, (3) [that] uses symbols in communication, and (4) [that] is collectively involved in crime” (Howell, 1998, p. 4). Wood and Alleyne (2010) note that the argument for including criminality as a criterion for defining gangs is compelling because the parties involved in studying gangs are mostly interested in the adverse criminal behavior associated with gang involvement. 4. Global trends in youth gang affiliation

3. Definition of youth gangs Assessing the scope of youth gang problems is challenging as there is little consensus among experts on what constitutes a gang or the defining features of youth gangs (Esbensen, Winfree, He, & Taylor, 2001; Howell, 1998). Varying definitions of gang involvement can lead to difficulties in measuring the scope and nature of gang problems, in identifying predictors of gang membership and the direction of strategies aimed at targeting youth gang problems (Esbensen et al., 2001). Overestimating or underestimating gang problems can influence the allocation of resources and give rise to inaccurate depictions of gangs that influence perceptions about the severity (or otherwise) of local gang problems (Matsuda, Esbensen, & Carson, 2012). A recent conceptualization developed through cross-national collaboration between gang researchers (the Eurogang network) specifies

The expansion of youth gangs across the United States (U.S.) is well documented. The number of U.S. cities reporting gang activity has grown exponentially since 1990 (Klein & Maxson, 2006). Research across the U.S. suggests that prevalence rates for youth gang membership vary between 2% and 37%, depending on the nature of the sampling population and the definition adopted (Klein & Maxson, 2006; Thornberry et al., 2003). However, the transmission of youth gangs and gang culture has not been confined to the U.S. Recent research has documented the global nature of gang activity, with studies reporting the existence of youth gangs in North and South America (Decker & Pyrooz, 2010), Europe (Gatti et al., 2011), Africa (Covey, 2010), Australia (White & Mason, 2006), and Asia (Pyrooz & Decker, 2012). Estimated prevalence rates for youth gang membership in Europe vary significantly across countries, from 0.4% of youth in Armenia to

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16.8% of youth in Ireland (Gatti et al., 2011). Likewise, the prevalence for gang membership in Asia varies widely. In a sample of 165 institutionalized youth offenders in Singapore, Chu et al. (2012) found that 35% of a sample of incarcerated youth could be classified as gangaffiliated offenders. In contrast, a study of 654 incarcerated youth offenders in China found that 47% had been convicted for gang-related crimes (Zhang, Messner, Lu, & Deng, 1997). Lower prevalence rates were found among a sample of 2163 school students in China; only 11.4% were classified as having either former or current gang involvement (Pyrooz & Decker, 2012). Importantly, the variation in prevalence estimates across these studies demonstrates how changing the definition of gangs or the sample population can dramatically influence prevalence rates. 4.1. Youth gang characteristics Although there have been some changes in the diversity and composition of youth gangs in recent years, the fundamental characteristics of youth gangs identified by Klein (1995) have remained relatively stable overtime, and contrast with stereotyped perceptions of gangs as large, highly organized and ritualized groups that control neighborhoods (Klein et al., 2006). Research suggests that while this may be true for some, in most street gangs “leadership is ephemeral, turnover is often high, and cohesiveness only moderate … [and] many street gangs are more a loose connection of cliques or social networks than a single, coherent whole” (Klein & Maxson, 2006, p. 164). Furthermore, involvement with gangs appears to be relatively fluid and transitory (Esbensen & Huizinga, 1993; Thornberry et al., 2003). Most youth who identify themselves as gang members report remaining in gangs for less than 4 years, with most being members for between 1 and 2 years (Gatti, Tremblay, Vitaro, & McDuff, 2005; Peterson, Taylor, & Esbensen, 2004; Thornberry et al., 2003); this is generally consistent outside of America too (e.g., Chu, Daffern, Thomas, Ang, Long, et al., submitted for publication; Gatti et al., 2011). The stereotypical image of youth gang members as young males, from ethnic or racial minorities, living in large cities or urban areas is somewhat supported by law enforcement data (Esbensen & Peterson, 2011). Challenging this image is information collected from large selfreport surveys, which suggests that approximately one-third of youth gang members are female, that gangs are emerging in nonurban areas, and that the racial and ethnic composition of gangs tends to mirror the community (Esbensen & Peterson, 2011). Consistent with information regarding the fluidity of gang ties, youth gang membership tends to peak in mid-late adolescence and then declines as youth transition into early adulthood (Zhang et al., 1997). 5. Gang membership, violence, and crime Various characteristics associated with delinquency consistently distinguish gang members from youth who never join gangs. The most enduring finding is that gang-affiliated youth commit more crimes (Klein & Maxson, 2006), especially violent, drug and weapon-related offenses, and are more delinquent than youth who have never been involved with gangs (Esbensen, Huizinga, & Weiher, 1993; Klein & Maxson, 2006). Additionally, youth gang membership is associated with a higher rate of offending, beyond the effect of having delinquent friends and after accounting for prior delinquency (Battin, Hill, Abbott, Catalano, & Hawkins, 1998). The relationship between gang involvement and offending is robust across a wide variety of gang definitions (Esbensen et al., 2001; Klein & Maxson, 2006), regardless of whether self-report or arrest data is used to measure offending (BattinPearson, Thornberry, Hawkins, & Krohn, 1998) and across countries reporting gang problems (Esbensen & Weerman, 2005; Gatti et al., 2005). Exploration of the specific relationship between gang involvement and criminal behavior reveals a progressive pattern of association;

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that is, the more restricted the definition of gang membership and the more intense the commitment to gangs, the stronger the differences are between gang and nongang youth crime patterns (Klein & Maxson, 2006). Esbensen et al. (2001) investigated differences in self-reported delinquency and five increasingly restrictive definitions of gang membership, ranging from all youth who claim gang membership at some point during their lifetime to only those youth who reported current core gang membership. Their study found that gang members reported increasing involvement in illegal activity as definitions became more restrictive. Similarly, varying levels of gang membership affect the strength of the gang–crime relationship. Current core gang members have the most serious offending profiles; youth who report being loosely associated with gangs or who have friends in gangs have lower offending rates than gang members, but higher rates than youth with no gang affiliation (Battin et al., 1998; Curry, Decker, & Egley, 2002). Extensive research using both longitudinal and cross-sectional design has led to the conclusion that “gang membership has an independent contributing role in the etiology of delinquency over and above other risk and protective factors” (Battin et al., 1998, p. 9). Although gang members contribute disproportionately to violent and general crime rates, and the differences between gang and nongang youth offending rates is most noticeable for serious and violent crimes (Esbensen & Huizinga, 1993), gangs do not specialize in violent offending to the exclusion of other types of offending. In fact, gang-related offending behavior is generalist in nature, and this includes significant involvement in both minor and serious delinquent acts such as drug use, public disorder and nuisance behaviors, property, drug-related and violent crimes (Esbensen & Weerman, 2005; Sharp et al., 2006; Thornberry, Krohn, Lizotte, & Chard-Wierschem, 1993). Research suggests that youth gangs have been found in almost all highly populated continents and that the association with crime and gang membership is strong across the globe (Pyrooz & Decker, 2012). However, patterns of involvement in crime vary between countries. The level of gang violence between countries appears to be influenced by access to firearms; higher gun violence is found in countries with greater access to firearms (Decker & Pyrooz, 2010). Asian gang youth are typically found to engage in less aggravated violence (e.g., assault, robbery and extortion offenses are most common) in comparison to American gang youth where shootings, gun violence, homicide, and aggravated assaults appear to be more common (Chin, 2000; Chu, Daffern, Thomas, & Lim, 2011; Tsunokai & Kposowa, 2002). 5.1. Interpreting the gang–crime relationship Research has demonstrated a strong association between gang membership and delinquency; however, few studies have clarified the processes involved in this relationship. Fagan (1990) noted that research was unable to identify whether differences in crime rates associated with gang membership reflected positive correlations between gangs and crime, features of gang processes, or due to social control mechanisms aimed at suppressing gang activity. Three competing models (i.e., selection, facilitation, and enhancement) have been proposed to account for the relationship (Thornberry et al., 2003). The selection model posits that gangs attract a particular “kind of person” and recruit members with a high propensity for delinquency, and who engage in criminal behavior regardless of their gang affiliation. If this model is accurate then gang members should have higher rates of delinquency than nongang members, and this pattern should be consistent across time (i.e., before, during, and after gang affiliation). In contrast, the facilitation model posits that gangs are a particular “kind of group” that promotes delinquency, and thus members are not intrinsically more delinquent than nonmembers prior to joining a gang. Gang membership is therefore considered to be a major cause of deviant behavior, with normative structures and group processes seen as significant facilitators of delinquency (Krohn & Thornberry, 2008). If this

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model is accurate then gang members should only have higher rates of delinquency during periods of active gang membership. Lastly, the enhancement model combines the two previous models and suggests that both selection and facilitation effects create an association between gang membership and delinquency. That is, gangs select members with a higher propensity for deviant behavior and the group dynamics of gangs enhances involvement in delinquent activities. This model posits that gang members will have higher rates of delinquency prior to joining gangs, and that rates of criminal behavior are particularly high during periods of active gang membership. The Rochester Youth Development Study (RYDS), which compared youth gang members to nongang members over three consecutive years from 15 to 17 years (Thornberry et al., 1993), found that rates of violent delinquency increased substantially when the youth joined gangs and decreased when they left the gang. Gang members, compared to nongang members, only showed significantly higher rates of violent behavior during periods of active membership, with a similar pattern observed for general delinquency (Thornberry et al., 1993), gun ownership and gun-crimes (Bjerregaard & Lizotte, 1995). A further examination of the RYDS data found evidence of a strong facilitation effect and a modest selection effect in predicting general delinquency, violence, drug use and drug sales, after controlling for six major risk factors for juvenile delinquency (Thornberry et al., 2003). Gatti et al. (2005) also found a strong association between gang membership and juvenile delinquency for youth aged 14―16 years that persisted even after controlling for pre-existing risk factors. Furthermore, their results suggested that a facilitation model best described the behavior of transient gang members (i.e., loosely affiliated members), while an enhancement model was most appropriate in describing the behavior of stable gang members. Consistent with these results, data from the Seattle Social Development Project also provide support for a facilitation model (Hill, Howell, Hawkins, & Battin-Pearson, 1999). Although rates of violent offending were slightly elevated among gang members in the year prior to active involvement with gangs, violent behavior increased substantially during gang membership, and dropped to baseline levels following exit from youth gangs. A recent study of 3700 school-aged youth (Melde & Esbensen, 2012) revealed that active gang membership was associated with a significant increase in the chances of participation in violence, whereas the propensity for violence was no longer different from nongang comparison groups once gang membership ceased. Youth who reported gang involvement were noted to have higher levels of general delinquency than comparison youth before, during and after periods of active gang membership, consistent with enhancement frameworks; in contrast to diminishing rates of violent offending following exit from gangs, levels of general offending remained elevated even after youth left the gang. Overall, Melde and Esbensen's analyses revealed that gang membership was associated with a greater increase in violence compared to general offending, suggesting that gang environments are “especially conducive to promoting violence” (p. 18). Several studies have found evidence for an enhancement effect. The Denver Youth Survey, a longitudinal study examining street offending and gang membership found gang members generally had higher rates of street offending compared to nongang members; and that involvement in street offending was substantially higher while adolescents were actively engaged in gangs (Esbensen & Huizinga, 1993). Furthermore, Gordon et al. (2004) found evidence of selection and socialization effects among a sample of 858 juveniles, followed in a 10-year longitudinal study. They observed that youth gang members, in comparison to nonmembers, had higher rates of delinquency prior to entering gangs; and found that involvement in drug, property, and violent offenses increased during periods of active gang membership, relative to levels of delinquent behavior prior to entering the gang. Overall, the evidence shows that juvenile delinquency varies as a function of gang membership, consistent with facilitation effects; and that offending behavior universally increases when youth join

gangs, are highest during periods of active membership, and typically decline after youth leave gangs (Krohn & Thornberry, 2008). 5.2. Risk factors for gang membership Several methodologically sound, prospective studies have identified a number of static (historical) and dynamic (changeable) variables that are associated with general delinquency, violent and serious offending (Farrington, 2002; Ferguson & Meehan, 2010; Howell, 2009). However, few studies have highlighted specific risk factors associated with gang activity (Esbensen, Peterson, Taylor, & Freng, 2009; Howell & Egley, 2005; Klein & Maxson, 2006; Thornberry et al., 2003). Most studies suggest that many risk factors predict both gang membership and violence, but few studies provide clear evidence about which factors (if any) uniquely predict gang membership (Esbensen et al., 2009). Typically, research that identifies predictors of youth gang membership, violent behavior or delinquency has categorized variables into one of five ecological domains: individual, family, peer, school and community. The risk factors that have been consistently demonstrated to predict adolescent violence and gang affiliation for each of these domains are summarized in Table 1. Although risk factors for gang affiliation and youth violence can be identified in all five domains, the relative importance of these risk factors for predicting gang affiliation varies according to the domain assessed (whereas risk factors for violence are seen consistently across the domains). There is clear evidence for a number of individual, family, and peer dynamic variables as risk factors for joining gangs, but only relatively weak and inconclusive evidence for school and neighborhood (community) factors in predicting gang membership (Klein & Maxson, 2006). The association between peer relationships and characteristics of peer groups and general youth delinquency is well established (Thornberry et al., 2003). Unsurprisingly then, involvement with delinquent peer networks, especially having friends who are involved with gangs (Curry & Spergel, 1992; Winfree, Backstrom, & Mays, 1994), and negative peer influences, have consistently emerged as strong, reliable predictors of gang membership (Esbensen et al., 1993; Klein & Maxson, 2006). Importantly, involvement with gangs and other antisocial peers tends to limit interactions with prosocial peers, which in turn limits opportunities for prosocial modeling and the development of networks that promote desistance from gangs and delinquent behavior (Pyrooz, Sweeten, & Piquero, 2012). Furthermore, adolescent peer networks have powerful effects on attitudes and behavior, and thus association with delinquent peers may facilitate involvement in gangs by both confirming and reinforcing antisocial beliefs (Esbensen et al., 1993; Klein & Maxson, 2006). In keeping with this argument, consistent evidence shows that youth attitudes supportive of delinquent behavior are significant predictors of gang membership (Klein & Maxson, 2006). Gang membership is associated with higher tolerance for deviance (Esbensen et al., 1993), more justifications and beliefs supportive of antisocial and violent behavior, and greater endorsement of progang attitudes (Winfree et al., 1994). For example, Chu et al. (2012) found that gang-affiliated youth offenders in Singapore had more favorable attitudes towards gangs, weapons, violence, and criminal associates than nongang-affiliated youth offenders. Similarly, evidence suggests prior involvement in deviant and problem behaviors such as drug and alcohol use (Thornberry et al., 1993), gun ownership for protection (Bjerregaard & Lizotte, 1995), serious and violent delinquency (Hill et al., 1999; Lahey, Gordon, Loeber, Stouthamer-Loeber, & Farrington, 1999), and prior contact with the juvenile justice system also predicted gang membership (Esbensen et al., 2009; Howell & Egley, 2005; Klein & Maxson, 2006; Thornberry et al., 2003). Other individual-level dimensions that have been found to be risk factors for gang participation include negative life experiences or events, and nondelinquent problem behaviors (e.g., reactivity, aggressiveness,

K. O’Brien et al. / Aggression and Violent Behavior 18 (2013) 417–425 Table 1 Risk factors for gang membership and youth violence. Domain

Risk factors for gang membership

Risk factors for youth violence

Individual

Negative life events * Low self-esteem Delinquent beliefs * Attitudes towards the future Internalizing behaviors (anxiety, withdrawal) Nondelinquent problem behaviors (externalizing behaviors) * Violence involvement General delinquency involvement Limited involvement in conventional activities

Peer

Characteristics of peer networks * Affective dimension of networks * Association with delinquent peers Commitment to delinquent peers Association with aggressive peers Poor parental supervision * Poor parental monitoring * Parenting style/hostile family environment Low attachment to parents/family Sibling antisocial behavior Family structure Family deviance

Early violence/aggression Involvement in nonviolent crime Conduct disorder/externalizing disorders Drug and alcohol use Impulsivity Risk taking/sensation seeking Beliefs supportive of violence Attributional bias Poor problem solving Poor concentration Attention deficits Low intelligence Low self-esteem Lack of empathy Poor social skills Negative/delinquent peer influences Alienation Absence of positive peers Gang involvement Lack of parental monitoring/ lack of clear guidelines Low parental involvement High permissiveness (parents) Severe or inconsistent discipline Parental attitudes regarding crime, violence and substance use Parental criminality/violence Physical abuse/neglect Parental conflict Parent separation Parent/child separation Low parental attachment/ bonding Delinquent siblings Large family size Involvement of supervisory services Poor academic performance Truancy Suspension Low school commitment Low attachment to or poor relationships with teachers Frequent school changes Poor quality school, overcrowding Poor classroom management Victim of violent crime High crime neighborhood/ violence exposure Availability of drugs and guns Exposure to racial prejudice Community disorganization Low community participation

Family

School

Low commitment to school/low educational aspirations Low school attachment Academic achievement Unsafe school environment

Community Criminogenic neighborhood indicators (e.g., drug use, youth in trouble) Neighborhood residents in poverty Availability of firearms

Sources: Dahlberg (1998); Derzon (2010); Hawkins et al. (1998); Howell and Egley (2005); Lipsey and Derzon (1998); Klein and Maxson (2006); Van der Merwe and Dawes (2007). Risk factors denoted with a * indicate characteristics that Klein and Maxson (2006) indicated have consistent or good support from past research.

or impulsivity) (Klein & Maxson, 2006). Although some recent studies have found that psychological factors (e.g., low self-esteem or depression, poor impulse control, low empathy, psychopathic personality traits, anxiety, and social withdrawal) increase the likelihood that youth will join gangs, other studies have not (Alleyne & Wood, 2010, 2011; Bjerregaard & Smith, 1993; Chu, Daffern, Thomas, Ang, & Long, submitted for publication; Dukes, Martinez, & Stein, 1997; Dupéré, Lacourse, Willms, Vitaro, & Tremblay, 2007; Esbensen et al., 1993; Hill et al., 1999).

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Some studies have found that family socioeconomic status (e.g., family poverty or economic disadvantage), structural family characteristics (e.g., single-parent households), parenting styles, and family member involvement with gangs are associated with gang membership (Chu, Daffern, Thomas, Ang, Long, et al., submitted for publication; Esbensen et al., 1993; Hill et al., 1999); however, the results across studies are inconsistent. Through an extensive review of the literature, Klein and Maxson (2006) concluded that poor parental monitoring and supervision were the only two reliable predictors of youth gang affiliation. With regard to school and neighborhood factors, failure in school, low school commitment and achievement, and presence of neighborhood gang activity have been identified as a source of risk for gang membership (Alleyne & Wood, 2011; Howell, 2009; Thornberry et al., 2003), but these findings were not consistent across studies (Bjerregaard & Smith, 1993; Klein & Maxson, 2006; Maxson, Whitlock, & Klein, 1998; Thornberry et al., 2003). 5.3. Risk factors for youth violence versus gang membership Most factors that predict youth violence are similar to those that predict gang membership. The key predictors of youth violence (distinct from predictors of general delinquency) include a history of prior violence, early onset of violent behavior, high levels of early aggression, low guilt, proviolent attitudes, and current substance use (Herrenkohl, Maguin, Hill, Hawkins, & Abbott, 2000; Loeber, Farrington, & Waschbusch, 1998; Tolan & Gorman-Smith, 1998). Given the close association between gang participation and violence, there is significant overlap between risk factors and developmental trajectories for involvement in violent and gang delinquency. To date, only one study has investigated the extent to which risk factors are shared between, or uniquely predict, gang membership compared to youth violence (Esbensen et al., 2009). In a study of 5395 school students, Esbensen et al. (2009) found that all 18 risk factors investigated were significantly associated with gang membership and violence, but none uniquely predicted gang membership. Ten risk factors independently predicted serious violent offending, after controlling for all other risks, whereas only six were independently related to gang membership (i.e., low guilt, neutralizations of delinquent behavior, association with and commitment to delinquent peers, drug and alcohol use, and negative school environments). Four variables were unique predictors of violence, but not gang membership: impulsivity, risk-seeking tendencies, few conventional peers, as well as unsupervised and unstructured peer associations. Despite similarities in risk factors, Esbensen et al. (2009) found that more risk factors were required before youth would join gangs as compared to becoming involved with violence, and that gang members experienced higher levels of risk (across and within all domains) than violent youth. 5.4. Patterns of risk prediction Beyond the identification of specific risk factors, four important trends regarding the association between risk factors and the likelihood of joining gangs have been delineated. First, risk factors for gang membership are seen within the five domains identified by past research on risks for general and violent delinquency, albeit the strength of the relationship varies across domains (Klein & Maxson, 2006). Second, although the relationship between risk factors and gang membership is not additive in the strict sense, the more risk factors for violence an individual possesses, the higher his or her likelihood of joining a gang (Esbensen et al., 2009; Klein & Maxson, 2006; Melde, Diem, & Drake, 2012). Moreover, individuals who present with risk factors in multiple domains typically pose greater risk than those with risk factors in only one domain (Thornberry et al., 2003; Wyrick & Howell, 2004). Even so, the presence of only one risk factor, if sufficiently deleterious within a given individual, can contribute to a high level of risk. Finally, although there are no risk factors that uniquely predict gang membership,

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research consistently demonstrates that gang-involved youth possess a high number of risk factors relative to nongang youth, and that they are rated as higher risk on structured assessment tools, in comparison to youth who never join gangs (Chu et al., 2012). It is also important to consider whether risk characteristics vary as a function of level or type of gang membership, as an affirmative answer would help to inform the development of targeted intervention programs (Klein & Maxson, 2006). However, few studies have investigated characteristic differences between youth who are core or stable gang members, in comparison to youth with more transient membership. Klein (1995) found little distinction between core and fringe gang members with regard to sociodemographic variables (e.g., family characteristics, age). However, differences in some psychological and behavioral variables were observed, with core gang members more likely to show lower impulse control, school performance and desire to change, higher group dependence and more antisocial attitudes than “fringe” gang members (Klein, 1995). Similarly, a number of other studies have found that core gang members do not differ demographically from other gang members, although earlier involvement with antisocial peers, early aggressive and violent behavior, greater endorsement of antisocial attitudes and participation in delinquent behaviors have been identified as consistent markers for stable or core gang membership (Battin-Pearson et al., 1998; Esbensen et al., 2001; Melde et al., 2012). These findings suggest that core gang members are particularly antisocial and aggressive; thus, intervention programs for entrenched gang members will need to focus on these cognitions and behaviors if they are to be effective. 5.5. Protective factors Research on protective factors against gang membership is still in its infancy, having developed at a much slower rate than investigation of characteristics that places youth at risk of joining gangs (Howell & Egley, 2005). Nevertheless, protective factors are important characteristics to investigate as they can shield at risk youth from engaging in delinquent activities. The broader juvenile delinquency literature suggests that problem behaviors occur when “individuals experience a preponderance of risk factors over protective factors in the major developmental domains” (Howell & Egley, 2005, p. 335). Although numerous characteristics have been proposed as possible protective factors that could discourage youth from gang activity, the extant literature does not provide a list of reliable protective factors (Howell, 2010). The few studies that exist suggest that: (a) increased parental monitoring and youth coping strategies (Maxson et al., 1998; McDaniel, 2012), (b) social skills, interactions with prosocial peers, and beliefs in moral order (Katz & Fox, 2010), (c) commitment to school, attachment to teachers and parents' expectations for school (Stoiber & Good, 1998; Thornberry, 2001), and (d) strong parental involvement and family cohesiveness (Li et al., 2002; Maxson et al., 1998), may operate as protective factors for gang membership. Further research is required before consensus is reached regarding the protective factors associated with youth gang participation. 6. Motivation for joining and desisting from gangs and persistence processes Although there is extensive research investigating the risk factors associated with gang involvement, few studies have shed light on motivations for joining gangs or the factors that promote retention in gangs or desistance from gang activity (Caldwell & Altschuler, 2001; Pyrooz & Decker, 2011). Decker and Van Winkle (1996) provide a framework for understanding the processes involved in decisions to join gangs, describing affiliation in terms of “pushes” (e.g., external forces that compel membership, such as the need for protection, following family or friends) and “pulls” (e.g., forces internal to gangs that attract membership, such as the desire for money, status or excitement). Other

important pull factors that may specifically motivate adolescents to join gangs include the expectation that gang-affiliated youth will gain status, identity and companionship (universal needs of young people) through membership (Alleyne & Wood, 2010; Klein, 1995; Klein & Maxson, 2006). Although push and pull factors may also contribute to the process of desistance, there is little research to clarify whether the factors associated with decisions to leave gangs are similar or different to the factors associated with the onset of gang membership (Melde et al., 2012; Pyrooz & Decker, 2011). The limited available evidence regarding motivation for engaging with gangs suggests that the “decision to join a gang is based on a multitude of factors, rather than a single decisive factor” (Decker & Curry, 2000, p. 476). A number of studies have indicated that friendshipbased reasons are strong motivators for gang membership (e.g., joining because friends are involved in gangs, to make friends, for company or due to an desire to be involved in group activities), as well as family ties to gangs, a desire to garner respect or to feel important, instrumental concerns such as requiring personal protection, and beliefs about the need to protect ones' neighborhood (Chu, Daffern, Thomas, Ang, Long, et al., submitted for publication; Decker & Curry, 2000). The reported motivation for joining gangs appears to be similar across levels of gang membership (e.g., in comparing current, former and associate gang members). The recurrent themes noted in this research suggest that friendship, respect, and being involved with a group are important motivations for gang membership, confirming perceptions that youth gangs are more likely to resemble friendship cliques than highly organized groups (Decker & Curry, 2000). Desistance from gang affiliation has traditionally been defined in “static”, absolute terms; that is, youth are either in a gang or not (Bushway, Thornberry, & Krohn, 2003). However, more recent conceptualizations have recognized that desistance involves a process of disengagement and a “severing of ties” (Pyrooz, Decker, & Webb, 2010), that unfolds over the life course (Bushway et al., 2003) and that ultimately leads to youth leaving gangs (Sweeten, Pyrooz, & Piquero, 2012). Consistent with this, Decker and Lauritsen (2002) found that gang desistance occurred in two ways: through abruptly leaving the gang (i.e., through severing ties and thus eliminating gang engagement and activity), or through gradual departure as part of the “developmental process” (i.e., slowly developing beliefs and engaging in activities that are counter to the gang). These two processes have been recognized in more recent studies of desistance (Pyrooz et al., 2010). Motivation for leaving gangs and desisting from gang activity vary across studies, but processes of maturation and ageing are often involved (Hastings, Dunbar, & Bania, 2011). As youth mature and assume other responsibilities in life, such as legitimate employment and having children, many appear to naturally transition away from gangs and navigate towards other social groups (Pyrooz & Decker, 2011). However, experiencing traumatic events (e.g., witnessing or personally experiencing violence) is also frequently cited as an important motivator for desistance (Decker & Lauritsen, 2002). Even though experiences of violence during initiation or ritual phases of gang membership often strengthen gang bonds and cohesion, there appears to be an upper limit of tolerance for most gang members (Decker & Van Winkle, 1996). That is, the impact of real violence on gang members and their families appears to provide a strong impetus for disengagement from gang activity. Rarely, however, are law enforcement motives or criminal justice sanctions reported as reasons for desisting from gangs, suggesting a mismatch between traditional gang control strategies and the reality of gang membership (Hastings et al., 2011). Common perceptions about gangs and their membership conjure up images of a “blood-in, blood-out” culture; few studies, however, support this viewpoint. Most gang members reported that they “just quit,” “walked away,” or left their gang without incident (Decker & Lauritsen, 2002; Decker & Van Winkle, 1996). Few gang members reported that the process of leaving gangs was structured or ceremonial, or report facing resistance when attempting to disengage from

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gang membership (Pyrooz & Decker, 2011). However, after renouncing membership, many youth maintain some social ties and attachments with their former gang. These ongoing ties appear to complicate the desistance process, by keeping youth connected with gang processes and activities. Research suggests that the greater the number of ties that youth maintain with former gangs, the longer it took to desist from gang activities and the more likely youth were to experience ongoing difficulties such as school disruption, engagement in delinquency and violent victimization (Pyrooz & Decker, 2011; Pyrooz et al., 2010). Furthermore, an added barrier to gang desistance involved the level of involvement youth had in their gang organization. Youth who were highly embedded and entrenched in the gang culture and dynamics typically found it more difficult to disengage from gangs and were, therefore, more likely to remain in gangs for prolonged periods of time (Pyrooz & Decker, 2011). Conversely, youth who were only weakly affiliated with gangs desisted at a faster rate and found it easier to leave their gangs. 7. Consequences of gang membership Gangs have powerful, enduring effects on the lives of adolescents who become involved with them, interfering with normal development and transitions to adulthood (Thornberry et al., 2003). Most notable and well researched are the long-term deleterious effects of adolescent involvement in deviant behavior. Research has clearly established that early delinquency predicts later disorder in the life course (Thornberry et al., 2003). In particular, adolescent deviancy has been associated with failure to complete schooling, parenthood in the teenage years, unemployment in early adult life, job instability, and ongoing participation in illegal activity (Krohn & Thornberry, 2008; Melde & Esbensen, 2011; Thornberry et al., 2003). Although gang membership is generally a short-term phenomenon for most young people, “its timing during the life course… [suggests it] may well have effects that cascade throughout the person's later development” (Krohn, Ward, Thornberry, Lizotte, & Chu, 2011, p. 995). However, few studies have directly examined the short- and long-term adverse consequences of gang membership, beyond the impact of involvement in criminal behavior (Krohn et al., 2011; Melde & Esbensen, 2011). More recently, several studies explored the short- and long-term noncriminal (e.g., social, economic, and relational effects) effects of gang activity, and whether membership of gangs constitutes a critical short-term transition that has adverse effects on longer-term life course trajectories (Melde & Esbensen, 2011). In a study of 1400 school-aged youth, Melde and Esbensen found that youth gang membership was associated with fewer prosocial peer interactions, lower school commitment, higher negative peer commitment, more unstructured socializing, greater acceptance of delinquent and aggressive behavior and more involvement with delinquent peers. Thus, the factors that put youth at risk for involvement with gangs and delinquent behavior appear to be accentuated through gang membership, thereby placing youth at further risk of deviating from conventional life trajectories (Melde et al., 2012). For example, youth who were disconnected from school prior to joining gangs, were observed to be even less committed to their studies after onset of gang participation, which increased the risk for school dropout (Melde & Esbensen, 2011). An ethnographic study by Levitt and Venkatesh (2001) showed that, at 9- to 10-year-follow-up, gang members reported lower educational attainment, higher rates of arrest and incarceration, and were more likely to receive income from illegal sources than nongang members. However, once background factors were statistically controlled, few differences remained, suggesting that gang membership was indirectly related to adverse outcomes later in life (e.g., gang membership influenced education attainment and incarceration, which in turn influenced prospects for legitimate work). Furthermore, a longitudinal study investigating differences in life outcomes for gang members found that stable gang members experienced significantly more

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difficulties during adolescence and early adulthood than both shortterm gang members and nonmembers (Thornberry et al., 2003). For example, gang members were more likely to drop out of school, to be teen parents, to experience unstable employment, and to be arrested as a young adult. Consistent with these results, Krohn et al. (2011) found that prolonged gang membership during early adolescence led to deleterious outcomes, including lower educational attainment and teen parenthood, which, in turn, was associated with more financial and familial problems during early adulthood. Ultimately, these cascading problems and difficulties in transitioning increased the probably of involvement in illegal behavior in adulthood. Importantly, the longer youth were involved with gangs, the more disruptions they experienced in later life (Krohn et al., 2011). In addition to increasing participation in criminal and delinquent behavior, gang members experience higher rates and more frequent experiences of serious violent victimization than nongang members (Peterson et al., 2004; Taylor, Peterson, Esbensen, & Freng, 2007). This may be due to: (a) retaliation from rival gangs, (b) violence experienced as a routine part of gang life, or (c) as part of violent initiation rituals (Decker & Van Winkle, 1996). Similar to patterns of participation in criminal behavior, research shows that violent victimization peaks during periods of active gang membership (Peterson et al., 2004). However, some researchers have highlighted a number of methodological limitations with this research and have questioned the directionality of the gang-victimization relationship (Gibson, Swatt, Miller, Jennings, & Gover, 2012). Few studies have taken account of preexisting differences between gang and nongang members, and thus most studies have been unable to clarify whether gang membership causes violent victimization, or whether these two experiences share common causes (Gibson, Miller, Jennings, Swatt, & Gover, 2009). Following a systematic review of the evidence, Gibson et al. (2012) acknowledged that there is a correlation between gang membership and violent victimization, but concluded that there is little evidence that joining a gang has a causal effect on victimization experiences. 8. Conclusion, limitations and future research This review has identified some important characteristics that operate as risk factors for youth gang membership and associated violence, and highlights a number of individual and contextual factors that increase the likelihood that youth at risk will engage in antisocial and violent behavior (Decker, Melde, & Pyrooz, 2012). The identification of risk factors specific to gang membership is crucial to the development of effective gang intervention strategies. Importantly, the characteristics, dynamics, and motivation to engage with peer networks emerged as a significant risk factor for gang affiliation, and thus needs to receive attention in gang prevention and intervention programs. Further, programs that focus exclusively on risk factors in only one domain (e.g., family or individual) will neglect important characteristics and processes present in other domains (Klein & Maxson, 2006). Therefore, gang intervention programs need to be multimodal and must address risk factors across multiple domains (Esbensen et al., 2009). One promising program is the Phoenix Gang Intervention Program. It is one of the few programs designed specifically to address multiple risk factors for gang-affiliated youth and to promote desistance from gang participation. The gang intervention program incorporates elements of cognitivebehavioral treatment and motivational interviewing, into evidencebased resources that can be utilized in both corrections and community settings (A.R. Phoenix Resources, 2012). Concomitantly, it is important to consider the role of protective factors and how these can help the youth desist from gang activities or buffer against the influence of gang-related risk factors. However, there is a lack of research in this area and we have yet to fully understand or disentangle the contribution of protective factors from those of the risk factors. In addition, drawing from strength-based approaches in offender rehabilitation (Whitehead, Ward, & Collie, 2007), further

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research on protective factors and strengths can also help improve prosocial, goal-directed behavior within these gang-affiliated youth that will ultimately assist with client engagement and future life satisfaction. Finally, despite the steady growth in research on youth gangs, there are a number of significant deficits and numerous methodological limitations in the extant literature. As mentioned previously, little is known about the dynamics and processes involved in gang development or the factors associated with desistance from gang membership (Howell, 2010). In fact, the field has only recently started to examine or formulate the psychological processes involved in gang affiliation and activities (e.g., Alleyne & Wood, 2010, 2011; Chu, Daffern, Thomas, Ang, & Long, submitted for publication; Chu, Daffern, Thomas, Ang, Long, et al., submitted for publication; Wood & Alleyne, 2010). Furthermore, the extensive body of research on gang affiliation has mostly involved cross-sectional designs, although a number of comprehensive longitudinal studies do exist. Some of the major limitations of current research include: (a) difficulties in distinguishing age effects from gang effects, (b) failure to include nongang comparison groups, and (c) difficulties in establishing the temporal order of variables regarded as risk factors for gang involvement and criminal behavior (Krohn & Thornberry, 2008). Future research should avoid these design problems and methodological limitations, which make causal inferences hazardous, potentially compromising the interventions upon which these studies are based.

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