IV. Theoretical Perspectives Linking Early-Life Aggression With Later-Life Crime
Because early-life aggression is such a strong predictor of adolescent delinquency and adult criminal behavior, any sound theory must be able to explain the rise of aggression in childhood, how aggression in childhood is linked to later-life crime, and why most aggressive children do not become criminal as adults. Most mainstream criminological theories collapse when they attempt to provide an explanation for these known behavioral patterns. There are, however, a handful of theories that hold some promise in their ability to explain some of these patterns. Two of the more influential theories—at least within mainstream criminology—are Michael Gottfredson and Travis Hirschi’s (1990) general theory of crime and Terrie Moffitt’s (1993) developmental taxonomy.
A. Gottfredson and Hirschi’s General Theory of Crime
In 1990, Gottfredson and Hirschi published a widely read and highly influential book titled A General Theory of Crime, in which they set forth a parsimonious and easily testable theory of crime. Unlike most criminological theories that focus almost exclusively on social factors, Gottfredson and Hirschi centered their attention on a psychological personality trait: low self-control. According to this theory, low levels of self-control are the cause of crime; delinquency; aggression; and analogous acts, such as smoking, drinking, and arriving late to class. Low self-control was defined through six different dimensions: (1) an inability to delay gratification, (2) a preference for simple tasks, (3) a penchant for risk seeking, (4) a preference for physical activities as opposed to mental ones, (5) an explosive temper, and (6) self-centeredness. Persons who score high on these six dimensions have, on average, relatively low levels of self-control and thus are at high risk for engaging in antisocial and criminal behaviors. A rich line of research has tested this proposition, and the results have been strikingly supportive of the theory. Indeed, of all the existing criminological theories, Gottfredson and Hirschi’s theory of low self-control is among the most empirically supported, and measures of low self-control are often the strongest predictors of delinquent acts.
It appears, then, that variation in individual levels of self-control is an important contributor to adolescent delinquency and adulthood crime. Still, the questions that remain are whether this theory can explain (a) aggression in childhood and (b) the link between early-life aggression and later offending behaviors. To address these issues, it is necessary to examine the nature of self-control.
Gottfredson and Hirschi (1990) maintained that self-control is engineered during childhood, typically by the ages of 8 to 10 years. Parents, according to the general theory, are the main agents responsible for shaping and molding their children’s level of self-control. Specifically, parents who monitor their children, recognize their children’s misbehavior, and punish their children’s transgression will raise, on balance, children with relatively high levels of self-control. Parents who fail to engage in these parenting techniques will, in general, raise children with comparatively low levels of self-control.
If this part of the theory is correct, then it takes about 8 to 10 years for parents to shape a child’s level of self-control. Moreover, it is not inconceivable to assume that most parents do not engage in much discipline before their children are approximately age 18 months. It is around this time that most children begin to display signs of aggression and consequentially is approximately the same time that most parents begin to punish and correct their child’s misbehavior. Over the course of the next few years, at least according to the logic of self-control theory, most parents will continue trying to blunt their children’s aggressive behaviors. Most children will respond to parental socialization, their use of aggression will subside, and between the ages of 5 to 8, their aggressive behavior will not be nearly as widespread as it was during early childhood. Parental socialization tactics thus might be able to explain the early age–crime curve set forth by Tremblay and his colleagues (2005).
During the time between childhood and early adolescence the use of aggression is not nearly as high as it was early in life. With the onset of adolescence, delinquent involvement begins to rise sharply to form the initial upswing in the more traditional age–crime curve. Proponents of Gottfredson and Hirschi’s (1990) theory argue that variations in self-control can also explain this age–crime curve. Although not well understood, and rarely studied, there is some reason to believe that levels of self-control are, on average, at their lowest during mid-to-late adolescence, around the same time that delinquent involvement is at its pinnacle. Near the end of adolescence and during early adulthood, levels of self-control begin to climb, which corresponds to the rapid drop in delinquency participation rates. The precise reasons for why levels of self-control change over time, however, are not known.
Also, it is important to note that the general theory places a relatively heavy emphasis on the role that criminal opportunities play in transforming low levels of self-control into a criminal act. If there is no crime opportunity available, then no one—not even persons with very low levels of self-control— will commit a crime. Thus, it is possible that there are more crime opportunities available during adolescence (especially because youths are able to escape the constant surveillance of their parents) than earlier in life (between the ages of 8 and 12 years). If this is the case, then self-control theory may be able to explain at least part of the age-graded nature of adolescent delinquent involvement.
The preceding discussion highlights the possible ways in which self-control theory can explain both the early age–crime curve and the later age–crime curve. However, can this theory also explain the stability in antisocial behaviors over time, including the link between early-life aggression and later-life crime? According to Gottfredson and Hirschi (1990), the answer is a resounding “Yes!” To understand their explanation of stability it is important to remember that levels of self-control purportedly emerge by around the age of 8 to 10. Furthermore, according to this theory, after levels of self-control are established, they remain relatively stable over the remainder of the life course. This means that a child with relatively low levels of self-control will mature into an adolescent with relatively low levels of self-control, who in turn will develop into an adult with relatively low levels of self-control. Given that low self-control is the cause of antisocial acts, including aggression and crime, then children with low self-control will be at risk for using aggression and, because they will develop into adolescents with low self-control, they will also be at risk for using aggression in adolescence. In adulthood, persons with low self-control will be apt to engage in aggression as well as criminal acts.
To recap, according to the general theory, the reason that aggression is prevalent during childhood is because self-control has not yet been acquired. As children age and as their parents socialize them, they begin to accumulate much higher levels of self-control. This emergence of self-control is accompanied by a concomitant drop in aggressive behaviors. Of course, not all children develop high levels of self-control, and those children who are typified by low levels of self-control are, according to Gottfredson and Hirschi (1990), the same children who are at greatest risk for continuing to engage in aggressive behaviors in adolescence, and they are also at great risk for engaging in criminal conduct during adulthood. Gottfredson and Hirschi’s theory of low self-control has the potential to explain the link between early-life aggression and later-life law-violating behaviors.
B. Moffitt’s Developmental Taxonomy
Moffitt’s (1993) developmental taxonomy is one of the most influential criminological theories advanced in recent years. One of the theory’s most noteworthy contributions is that, instead of treating all offenders as having the same developmental pathways, Moffitt recognized that there were at least two different types of offenders, each with their own unique etiology. The first type of offender, which she labeled life-course-persistent (LCP) offenders, begins to display signs of antisocial behavior, including aggression, early in life, often well before the age of 2. LCP offenders, according to the theory, persist with their antisocial behaviors throughout childhood and, during adolescence, they engage in all different types of delinquent acts, ranging from very minor (e.g., underage drinking) to very serious (e.g., assault and robbery). As adults, LCP offenders continue their violent behaviors and criminal conduct; as a result, they often spend a considerable amount of time incarcerated. Approximately 6% of all males are considered LCP offenders, and there is debate over whether there are any female LCP offenders. Although LCP offenders comprise only a relatively small percentage of the population, they make up a disproportionate amount of all crimes, and they are responsible for the majority of all violent crimes.
According to Moffitt (1993), two interrelated factors are responsible for producing LCP offenders. First, LCP offenders are born with neuropsychological deficits. These neuropsychological deficits can be the result of birth complications, exposure to toxins in utero, genetics, or a range of other factors. Second, LCP offenders are born into adverse, criminogenic family environments, where their parents may be abusive, cold and withdrawn, or emotionally detached. To understand how these two factors (i.e., neuropsychological deficits and an adverse family environment) work together to produce LCP offenders it is important to recognize that children born with neuropsychological deficits are often challenging to care for; they tend to be fussy and socially taxing, and they typically have difficult temperaments. Parents who are warm, loving, caring, and attached to their children are often in a position to override the problem behaviors displayed by children with neuropsychological deficits. Some children with neuropsychological deficits, in contrast, are born into criminogenic family environments where their parents are not well equipped with the necessary skills needed to overcome the difficult nature of their child. Over time, the family environment exacerbates the antisocial behaviors of children with neuropsychological impairments, thereby setting the child onto an antisocial pathway that ultimately culminates in the creation of an LCP offender.
Moffitt’s explanation of LCP offenders also has the ability to explain the association between aggression in childhood and crime in adulthood. LCP offenders show extremely high levels of behavioral stability, wherein early-life aggression is associated with serious physical violence in adolescence, followed by criminal involvement during adulthood. Moffitt explained the stable antisocial behavioral patterns of LCP offenders by focusing on transactional processes that occur between the difficult temperaments of LCP offenders and the environment. In brief, aggressive temperaments propel LCP offenders into certain criminogenic situations. For example, highly aggressive children often have difficulties excelling in school, which may lead to difficulties excelling in school during adolescence. LCP offenders, because of their problems at school, may drop out or, if they do graduate, face career prospects that often are circumvented and not very promising. As adults, then, LCP offenders are somewhat “knifed off ” from conventional society, thereby embedding them even further into an antisocial lifestyle where behavioral change is unlikely to occur.
Because only a small fraction of all persons would be considered LCP offenders, Moffitt was left to explain why rates of delinquent involvement are so high during adolescence. To answer this question, she identified a second class of offenders, which she termed adolescence-limited (AL) offenders. AL offenders do not display antisocial tendencies in childhood; neither do they engage in criminal behaviors during adulthood. Unlike LCP offenders, who engage in antisocial behaviors at all stages of the life course, AL offenders confine their offending behaviors to adolescence, and their delinquent acts are much less serious than those committed by LCP offenders. The types of delinquent behaviors that most AL offenders commit are relatively minor and mostly include status offenses (e.g., underage drinking, truancy) or other forms of minor delinquency (e.g., petty theft). Most youth would be considered AL offenders because the majority of adolescents dabble in delinquency but are not antisocial as children and never commit a crime in adulthood.
Moffitt (1993) provided a unique and provocative explanation for the factors that contribute to the development of AL offenders. Unlike LCP offenders, who suffer from neuropsychological deficits and an adverse home environment, AL offenders engage in delinquency because of what Moffitt called the maturity gap. The maturity gap, according to Moffitt, captures the disjuncture that exists between biological maturity and social maturity for adolescents. Most adolescents would be considered biologically mature in the sense that they are capable of reproducing. In historical times, youth around the age of 13 did, in fact, begin to marry and produce offspring. They were also afforded the same rights and privileges that were extended to adults. In other words, their biological maturity was matched to their social maturity. In contemporary times, in most industrialized countries, however, adolescents are subjected to a series of laws and rules that adults are not. These regulations limit youths’ ability to partake in adult behaviors. Adolescents in the United States, for example, are not allowed to drive a car until they turn 16 years old, they are not allowed to vote until they turn 18, and they may be required to attend school until a certain age. The end result is a gap between biological maturity (i.e., they are able to reproduce) and social maturity (i.e., society places limits on their privileges) in which adolescents are trapped.
The maturity gap creates dissonance in adolescents and, as a result, they search out ways (unconsciously) to reduce the disjuncture between their biological maturity and their social immaturity. To do so, they turn their attention to LCP offenders. LCP offenders live their lives with a total disregard for rules. They skip school, drink alcohol, have promiscuous sex, and basically thumb their nose at any and all regulations that seek to limit their freedom. In many ways, then, they engage in minor acts of delinquency that are reminiscent of “adult-like” behaviors (e.g., drinking alcohol, not going to school). To reduce the maturity gap, AL offenders mimic these adult-like behaviors being displayed by LCP offenders. By doing so, AL offenders increase their social maturity and erase, at least in part, the disjuncture between biological maturity and social immaturity. As adolescents mature into adults, they begin to be afforded the same privileges that are bestowed to adults. Maturation thus eliminates the maturity gap and, consequentially, delinquent involvement decreases appreciably as adolescents become adults.
Moffitt’s (1993) theoretical perspective has the potential to explain the conventional age–crime curve, but can it also explain the newer age–crime curve discovered by Tremblay and associates (1999, 2005)? Even though Moffitt did not directly confront this issue when setting forth her theory, there is some reason to believe that the developmental taxonomy may be able to shed some light on the early age–crime curve. During childhood, LCP offenders obviously display various signs of antisocial behaviors, including aggression. According to Moffitt’s theory, however, AL offenders do not show any signs of aggression early in life. Thus, the developmental taxonomy is able to explain why LCP offenders use aggression in childhood, but it is not able to explain why almost all children, including AL offenders, use aggression. Moreover, Moffitt’s theory does lend itself to an explanation of why aggressive behaviors decline around age 3 only to reappear once again in adolescence. Overall, however, the developmental taxonomy provides some needed insight into how aggressive behaviors in childhood may be tied to criminal behaviors later in life.