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129 In February of 1991, Stephen Mobley walked into a Domino’s Pizza store in Georgia to rob it. Once he got the money, Mobley forced store manager John Collins onto his knees and shot him execution style. In the automatic appeal to the Georgia Supreme Court to get his sen- tenced commuted to life in prison, his primary defense boiled down to claiming that “my genes made me do it.” In support of this defense, Mobley’s lawyers pointed to a Dutch study of an extended family in which for generations many of the men had histories of unprovoked violence. The researchers took DNA samples from 24 male members of the family and found that those with violent records had a marker for a mutant or variation of a gene for the manufacture of monoamine oxydase A (MAOA), an enzyme that regulates a lot of brain chemicals. Mobley’s lawyers found a similar pattern of violent behavior and criminal convic- tions among his male relatives across the generations and requested funds from the court to conduct genetic tests on Mobley to see if he had the same genetic variant. The court wisely denied the defense motion. Even if it were found that Mobley had the same genetic variant, it would not show that he lacked the substantial capacity to appreciate the wrongfulness of his acts or to conform to the requirements of the law. Mobley’s lawyers were hoping to mitigate his sentence by appealing to a sort of genetic determinism that simply does not exist. As we shall see in this section, genes don’t “make” us do anything; they simply bias us in one direction rather than another. Except in cases of extreme mental disease or defect, we are always legally and morally responsible for our behavior. Cases such as Mobley’s underline the urgent need for criminologists to understand the role of genes in human behavior as that role is understood by geneticists.
Biosocial Approaches Biosocial Approaches
130 CRIMINOLOGY: THE ESSENTIALS
y The Biosocial Approach
Biosocial theories have not been popular with mainstream social scientists until fairly recently because they were interpreted as a sort of “biological determinism.” This kind of thinking is rarer today as social scien- tists have become more sophisticated in their thinking about the interaction of biology and the environ- ment (M. Robinson, 2004). There are still people who fear that “biological” theories can be used for racist ends, but as Bryan Vila (1994) remarks, “Findings can be used for racist or eugenic ends only if we allow perpetuation of the ignorance that underlies these arguments” (p. 329). Bigots and hate mongers will climb aboard any vehicle that gives their prejudices a free ride, and they have done so for centuries before genes were heard of. Biosocial criminologists believe that because humans have brains, genes, hormones, and an evolution- ary history, they should integrate insights from the disciplines that study these things into their theories and dismiss naïve nature versus nurture arguments in favor of nature via nurture. Any trait, characteristic, or behavior of any living thing is always the result of biological factors interacting with environmental factors (Cartwright, 2000), which is why we call modern biologically informed criminology biosocial rather than biological. In many ways, the early positivists were biosocial in approach because they explicitly envisioned biological and environmental interaction. Their ideas and methods were primitive by today’s standards, but then, so were the ideas and methods of most sciences in the 19th century. Evolutionary ideas about the behavior of all animals (especially the human animal) were poorly understood; genes were unheard of, and the brain was still a mysterious locked black box. This has all changed with the sequencing of the human genome and with the advent of machines that enable us to see what is going on in the brain as we think and act. For these and other reasons, biosocial research into criminality is proceeding at an explosive pace. As Lilly et al. (2007) maintain, “It is clear that the time has arrived for criminologists to abandon their ideo- logical distaste for biological theories” (p. 304).
y Behavior Genetics
Behavior genetics is a branch of genetics that studies the relative contributions of heredity and environ- ment to behavioral and personality characteristics. Genes and environments work together to develop all the traits—height, weight, IQ, impulsiveness, blood sugar levels, blood pressure, and so on—the sum of which constitutes the person. Behavior geneticists stress that genes do not cause us to behave or feel; they simply facilitate tendencies or dispositions to respond to environments in one way rather than in another. There are no genes “for” criminal behavior, but there are genes that lead to particular traits such as low empathy, low IQ, and impul- siveness that increase the probability of criminal behavior when combined with the right environments. Geneticists use twin and adoption studies to disentangle the relative influences of genes and environ- ments, and they tell us that genes and environments are always jointly responsible for any human charac- teristic. To ask whether genes or environment is most important for a given trait is just as nonsensical as asking whether height or width is most important to the area of a rectangle. Gene expression always depends on the environment (think of identical rose seeds planted in an English garden and in the Nevada desert, and then think about where the full genetic potential of the seeds will be realized). Behavior geneticists quantify the extent to which genes influence a trait with a measure called heritability (symbolized as h^2 ), which ranges between 0 and 1. The closer h^2 is to 1.0, the more of the variance (difference) in a trait in a population, not in an individual, is due to genetic factors. Since any
132 CRIMINOLOGY: THE ESSENTIALS Evocative rGE thus serves to magnify phenotypic differences by funneling individuals into like-minded peer groups (“birds of a feather flock together”). Active rGE refers to the active seeking of environments compatible with our genetic dispositions. Active rGE becomes more pertinent as we mature and acquire the ability to take greater control of our lives because within the range of possibilities available in our cultures, our genes help to determine what fea- tures of the environment will and will not be attractive to us. Active rGE assures us that our minds and personalities are not simply products of external forces, and that our choices are not just passive responses to social forces and situations. We are active agents who create our own environments just as they help to create us. Genes imply human self-determination because, after all, our genes are our genes. As Colin Badcock (2000) put it, “Genes don’t deny human freedom; they positively guarantee it” (p. 71). Genes are constantly at our beck and call, extracting information from the environment and manufacturing the substances we need to navigate it. They are also what make us uniquely ourselves and thus resistant to environmental influences that grate against our natures. In short, genes do not constrain us; they enable us. This view of humanity is more respectful of human dignity than the blank slate view that we are putty in the hands of the environmental winds.
Behavior Genetics and Criminal Behavior
Although there are no genetic theories of criminal behavior per se, behavior genetic studies help us to better understand traditional criminological theories. For instance, large behavior genetic studies conducted in the United States (Cleveland et al., 2000) and the UK (Moffitt & the E-Risk Study Team, 2002) have shown that genetic factors play a large part in sorting individuals into different family structures (broken vs. intact homes), a variable often linked to antisocial behavior. In both these studies, families consisting of a divorced or never-married mother with children fathered by different men are the most at-risk family type for anti- social behavior, and families with full siblings with both biological parents present were least at risk, as noted in Chapter 7. Genes, of course, contribute to the choices people make, as well as make people easy or difficult to live with. One of those genetic factors is almost certainly low self-control. As we saw in Chapter 5, Gottfredson and Hirschi (1990) attributed low self-control exclusively to parental treatment. However, there are now well over 100 studies that have shown rather strong links between low self-control and low levels of the neu- rotransmitter serotonin (Crockett, Clark, Lieberman, Tabinia, & Robbins, 2010). In other words, while we all have to be taught to control our impulses, some of us are naturally easier to teach than others. Levels of serotonin are governed both by genes and by the environment. That is, genes govern the base levels of sero- tonin a person has, but what is going on in the environment results in serotonin levels increasing and decreasing (J. Wright, 2011). Unlike the relatively strong genetic influences discovered for most human traits, genetic influences on antisocial behavior are modest, especially during the teenage years. A study of 3,226 twin pairs found that genes accounted for only 7% of the variance in antisocial behavior among juvenile offenders, but 43% among adult offenders (Lyons et al., 1995). Heritability coefficients for most traits related to antisocial behavior are typically in the .30 to .80 range, and for antisocial behavior itself, two meta-analyses concluded that they are in the .40 to .58 range (Ferguson, 2010; Rhee & Waldman, 2002), with h² being higher in adult than in juvenile populations. What this means is that the majority of delinquents have little if any genetic vulnerability to criminal behavior, while a small minority may have considerable vulnerability. Pooling these two groups has the effect of elevating estimates of the overall influence of genes while minimizing it
Chapter 8. Biosocial Approaches 133 for those most seriously involved. Strong genetic effects on antisocial behavior are most likely to be found only among chronic offenders who begin offending prior to puberty and who continue to do so across the life course (Moffitt & Walsh, 2003).
y Molecular Genetics
Heritability estimates only tell us that genes are contributing to a trait, but they do not tell us which genes; only molecular genetics can tell us this. Fortunately, we can now go straight to the DNA (DNA is the acid in the nucleus of our cells that contains the instructions for particular genes, which in turn directs the manufac- ture of the substances we all need to survive and function) by genotyping the individuals with a simple cheek swab. We can then do an analysis of the effects of certain genes on individuals who have them and compare it with people who do not. Molecular genetic studies are being conducted with increasing frequency in criminology, with the huge National Longitudinal Study of Adolescent Health (ADD Health) study being one yielding some very important genetic findings. It is important to emphasize that any individual gene accounts only for a miniscule proportion of the variance in criminal behavior, and that it contributes to a trait linked to criminality, not to criminality itself, which you remember is a composite of many different traits. Genes always have indirect effects on behavior via the effects of the proteins they make on human traits and abilities. All people in the world have the same genes that make them human, but we all have slight variations of them that make us all different (except for identical twins). If we didn’t have these differences, the police in all those crime scene investigation shows would not be able to identify suspects by the bodily fluids left behind at crime scenes. For instance, although we all have genes that make blood, we have different blood types. Differences among individuals in behavioral traits are partially the result of what geneticists call genetic polymorphisms. Polymorphisms are differences in DNA sequences that code for the same gene, but which may make more or less of the substance (say, low serotonin), which leads to slightly different functional or physical traits among individuals. Let us return to Mobley’s “my MAOA gene made me do it” argument in the opening vignette to illustrate how geneticists study the effects of these gene variants. A major longitudinal study of maltreatment looking at the role of the MAOA gene showed why only about one half of abused/neglected children become violent adults (Caspi et al., 2002). The MAOA gene comes in variants that genetics call “high” and “low” activity. For a variety of reasons we cannot get into here, the low-activity version is a risk factor for a number of behavioral problems, and the high-activity version is a protective factor. Neither the genetic risk nor environmental risk factors by themselves had much effect on antisocial behavior. When combined, however, the odds of having a verified arrest for a violent crime for those with both genetic (the low variant of the MAOA gene) and environmental (maltreatment) risk factors were found to be 9.8 times greater than the odds for subjects with neither the genetic nor the environmental risk. Furthermore, although the low MAOA + maltreatment subjects were only 12% of the cohort, they were responsible for 44% of its criminal convictions. The overall conclusion arrived at by a meta-analysis of the MAOA/maltreatment research was that their interaction is a significant predictor of antisocial behavior across all studies (Kim-Cohen et al., 2006). However, a study by Widom and Brzustowicz (2006) found that while the high-activity MAOA allele (an alternate form of a gene at the same location on a chromosome) buffered whites from the effects of childhood abuse and neglect as it relates to antisocial behavior later in life, it did not protect nonwhites. The authors suggest that other environmental stressors, such as the high density of antisocial others in the neighborhood, may have negated the protective power of the high-activity polymorphism among nonwhites
Chapter 8. Biosocial Approaches 135 becomes a less rational strategy because cooperators remember and retaliate against those who have cheated them. Ultimately, cooperation is the most rational strategy in any social species because each player reaps in the future what he or she has sown in the past. Yet, we continue to see cheating behavior despite threats of exposure and retaliation. We do so because exposure and retaliation are threats only if cheats must operate within the same environment in which their reputations are known. Cheats can move from location to location, meeting and cheating a series of others who are unaware of their reputation. This is the pattern of many career criminals who move from place to place, job to job, and relationship to relationship, leaving a trail of misery behind them before their reputa- tion catches up. This is why cheats are more likely to prosper in large cities in modern societies than in small traditional communities where the threat of exposure and retaliation is great (Ellis & Walsh, 1997). Of course, the stability of the group and cultural dynamics must be considered. In communities where a “badass” reputation is valued by males more than anything else, criminal behavior is almost a constant thing. Even in these unstable communities containing large numbers of chronic cheats, there must be a certain level of group loyalty and cooperation.
The Evolution of Criminal Traits
There are a number of evolutionary theories of crime, all of which focus on reproductive strategies. This is not surprising because from a biological point of view, the evolutionary imperative of all living things is reproductive success. There are two ways that members of any animal species can maximize reproductive success: parenting effort and mating effort. Parenting effort is the proportion of reproductive effort invested in rearing offspring, and mating effort is that proportion of effort allotted to acquiring sexual ▲ Photo 8.2 A concentration on parenting effort is strongly associated with a prosocial lifestyle; a concentration on mating effort is strongly associated with an antisocial lifestyle.
136 CRIMINOLOGY: THE ESSENTIALS partners. Because humans are born more dependent than any other animal, parenting effort is particularly important to our species. The most useful traits underlying parenting effort are altruism, empathy, nurtur- ance, and intelligence (Rowe, 2002). Humans invest more in parenting effort than any other species, but there is considerable variation within the species. Gender constitutes the largest division due to different levels of obligatory parental investment between the genders. Female parental investment necessarily requires an enormous expenditure of time and energy, but the only obligatory investment of males is the time and energy spent copulating. Reproductive success for males increases in proportion to the number of females to whom they have sexual access, and thus males have an evolved propensity to seek multiple partners. Mating effort emphasizes quantity over quality (maximizing the number of offspring rather than nurturing a few), although maxi- mizing offspring numbers is obviously not a conscious motive of any male seeking sex. The proximate motivation is sexual pleasure, with more offspring being a natural consequence (in pre-contraceptive days) when the strategy proved successful. Reproductive success among our ancestral females rested primarily on their ability to secure mates to assist them in raising offspring in exchange for exclusive sexual access, and thus human females evolved a much more discriminating attitude about sexual behavior (Geary, 2000). According to evolutionary biolo- gists, the inherent conflict between the reckless and indiscriminate male mating strategy and the careful and discriminating female mating strategy drove the evolution of traits such as aggressiveness, and the lowering of trait levels (relative to female levels) such as empathy and constraint that help males to over- come both male competitors and female reluctance. The important point to remember is that although these traits were designed by natural selection to facilitate mating effort, they are also useful in gaining non- sexual resources via illegitimate means (Quinsey, 2002; Walsh, 2006). The reverse is also true—traits that facilitate parenting effort underlie other forms of prosocial activity: “crime can be identified with the behaviors that tend to promote mating effort and noncrime with those that tend to promote parenting effort” (Rowe, 1996, p. 270). Because female reproductive success hinges more on parenting effort than mating effort, females have evolved higher levels of the traits that facilitate it (e.g., empathy and altruism), and lower levels of traits unfavorable to it (e.g., aggressiveness) than males. Of course, both males and females engage in both mating and parenting strategies, and both genders follow a mixed mating strategy. It is only claimed that mating behavior is more typical of males and parenting effort is more typical of females. Empirical research supports the notion that an excessive concentration on mating effort is linked to criminal behavior. A review of 51 studies relating number of sex partners to criminal behavior found 50 of them to be positive, and in another review of 31 studies it was found that age of onset of sexual behavior was negatively related to criminal behavior (the earlier the age of onset, the greater the criminal activity) in all 31 (Ellis & Walsh, 2000). A British cohort study found that the most antisocial 10% of males in the cohort fathered 27% of the children (Jaffee, Moffitt, Caspi, & Taylor, 2003), and anthropologists tell us that there are striking differences in behavior between members of cultures that emphasize either parenting or mating strategies. Cultures emphasizing mating effort the world over exhibit behaviors (low-level parental care, hyper-masculinity, transient bonding) considered antisocial in Western societies (Ember & Ember, 1998). Molecular genetic studies also find significant relationships between sexual and criminal behavior. A study by Beaver, Wright, and Walsh (2008) tested the evolutionary claim that the most antisocial indi- viduals should have the largest number of sexual partners. They found that the same polymorphism of the dopamine (a neurotransmitter discussed in the next section) transporter gene (DAT1) that was
138 CRIMINOLOGY: THE ESSENTIALS and forth across the brain. Information from the environment is received from thousands of dendrites (the little finger-like projections in the figure), summated in the body of the neuron, and passed on electrically down the axon (the longer projection from the neuron in the figure). When the impulse reaches the end of the axon, it releases the neurotransmitters across the synaptic gap to further relay the message. The most important thing to remember here is that more “primitive” networks that control vital functions such as breathing and heart rate come “hardwired” at birth, but development of the higher brain areas depends a lot on environmental “software” downloaded after birth. The message neuroscience has for us is that the experi- ences we encounter largely determine the patterns of our neuronal connections, and thus our ability to success- fully navigate our lives (Quartz & Sejnowski, 1997). Figure 8.1 Neurons, Axons, Dendrites, and the Synaptic Process Source: National Institute on Aging website. Available at http://www.nia.nih.gov/Alzheimers/Publications/UnravelingtheMystery/
Chapter 8. Biosocial Approaches 139 Neural networks are continually being made and selected for retention or elimination in a “use it or lose it” process governed by the strength and frequency of experience. Retention is biased in favor of networks that are most stimulated during early development (Restak, 2001). This is why bonding and attachment are so vital to human beings, and why abuse and neglect are so injurious. Hormones released by chronic stress can cause neurons to die, and children with high levels of these hormones experience cognitive and social development delays (M. Robinson, 2004). As Perry and Pollard (1998) point out, “Experience in adults alters the organized brain, but in infants and children it organizes the developing brain” (p. 36). Brains organized by stressful and traumatic events tend to relay events along the same brain pathways laid out by early events because pathways laid down early in life are more resistant to elimination than pathways laid down later in life. A brain organized by negative events is ripe for antisocial behavior.
Reward Dominance and Prefrontal Dysfunction Theories
If social animals are to function normally in their social groups, they must possess the ability to respond to signals of reward and punishment with socially appropriate approach and avoidance behavior. Reward dominance theory is a neurological theory based on the proposition that behavior is regulated by two opposing mechanisms, the behavioral activating (or approach) system (BAS) and the behavioral inhi- bition system (BIS). The BAS is associated with the neurotransmitter dopamine and with pleasure areas in the brain (Gove & Wilmoth, 2003). The BIS is associated with serotonin and with brain structures that govern memory. Neurotransmitters such as dopamine and serotonin are the chemical messengers that shunt information between neural networks. Dopamine facilitates goal-directed behavior, and serotonin generally modulates behavior (Depue & Collins, 1999). The BAS is sensitive to reward and can be likened to an accelerator motivating a person to seek reward- ing stimuli. The BIS is sensitive to threats of punishment and can be likened to a brake that stops a person from going too far too fast. The BAS motivates us to seek whatever affords us pleasure, and the BIS tells us when we have had enough for our own good. A normal BAS combined with a faulty BIS, or vice versa, may lead to a very impulsive person with a “craving brain” that can lead him or her into all sorts of physical, social, moral, and legal difficulties, by becoming addicted to pleasures such as food, gambling, sex, alcohol, and drugs (Day & Carelli, 2007). While most of us are more or less equally sensitive to both reward and punishment (BAS/BIS balance), in some people one system might dominate the other most of the time. The theory asserts that criminals, especially chronic criminals, have a dominant BAS, which tends to make them overly sensitive to reward cues and relatively insensitive to punishment cues (Day & Carelli, 2007). Reward dominance theory provides us with hard physical evidence relating to the concepts of sensation seeking, impulsiveness, and low self- control we have previously discussed, since each of these traits is undergirded by either a sticky accelerator (not enough dopamine) or faulty brakes (low serotonin). A third system of behavior control is the fight or flight system (FFS), chemically controlled by the adre- nal hormone and neurotransmitter epinephrine (adrenaline). The FFS is that part of the autonomic nervous system that mobilizes the body for vigorous action in response to threats by pumping out epinephrine. Fear and anxiety at the chemical level are epinephrine shouting its warning: “Attention, danger ahead; take action to avoid!” Having a weak FFS that whispers rather than shouts combined with a BAS that keeps shouting, “Go get it!” and a BIS too feeble to object, is obviously very useful when pursuing all kinds of antisocial activities. Another neurologically specific theory of criminal behavior is prefrontal dysfunction theory. The pre- frontal cortex (PFC) is a part of the brain located just above the eyes that occupies about one third of the human cerebral cortex, and has been called “the most uniquely human of all brain structures” (Goldberg, 2001, p. 2).
Chapter 8. Biosocial Approaches 141 Table 8.1 Summarizing Biosocial Perspectives and Theories Theory Key Concepts Strengths Weaknesses Behavior and Molecular Genetics Genes affect behavior in interaction with environmental influences. Heritability estimates the relative contribution of genetic and environmental factors and traits affecting criminality. All individual traits are at least modestly influenced by genes. Looks at both the genetic and environmental risk factors for criminal behavior. Understanding genetic contributions and also identifies the contributions of the environment. Provides “hard” evidence. Requires twin samples and/or adoptees, which are difficult to come by. However, technology now enables us to go straight to the DNA in molecular genetics. Expensive and requires cooperation of lab scientists. Evolutionary Psychology Perspective Human behavior is rooted in evolutionary history. Natural selection has favored victimizing tendencies in humans, especially males. These tendencies arose to facilitate mating effort, but are useful in pursuing criminal behavior as well. Criminals emphasize mating effort over parenting effort more than males in general. Ties criminology to evolutionary biology. Mating effort helps to explain why males are more criminal than females and why criminals tend to be more sexually promiscuous than persons in general. Emphasizes that crime is biologically “normal” (although regrettable) rather than pathological. Gives some the impression that because crime is considered “normal,” it is justified or excused. Makes assumptions about human nature that may or may not be true. While recognizing that culture is important, it tends to ignore it. There are a number of neurological disorders that result from mothers drinking alcohol while pregnant, the most serious of which is fetal alcohol syndrome (FAS). FAS is a chronic condition resulting from an individual’s prenatal alcohol exposure. Prenatal exposure to alcohol disrupts the migration and hookup of the embryo/fetus’s developing neurons in brain areas such as the frontal lobes (Goodlett, Horn, & Zhou, 2005). The behavioral symptoms of FAS include low IQ; hyperactivity; impulsiveness; poor social, emo- tional, and moral development; and a predisposition to alcoholism (Walsh & Yun, 2011). There are many other substances that have similar effects on neuron development and migration, because whatever the mother ingests, so does her embryo/fetus. A common risk factor is maternal smok- ing, which puts her fetus at risk for hypoxia (intermittent reduction of oxygen available to the fetus that may lead to brain cell death) (Zechel et al., 2005) as well as the toxic chemical components of tobacco (Huizink & Mulder, 2006). Cohort studies (e.g., Brennan, Grekin, & Sarnoff, 1999) consistently find that maternal smoking during pregnancy predicts criminal behavior in offspring independent of other factors. A review of a number of such studies found significantly increased risk for fetal tobacco-exposed indi- viduals versus nonexposed individuals for various forms of antisocial behavior across diverse contexts and independent of other factors such as maternal SES and IQ (Wakschlag, Pickett, Cook, Benowitz, & Leventhal, 2002). Table 8.1 summarizes the key concepts and strengths and weaknesses of biosocial perspectives and theories. (Continued)
142 CRIMINOLOGY: THE ESSENTIALS
y Evaluation of the Biosocial Perspective
Lilly et al. (2007) note that the most dramatic developments in science come most often from new obser- vational techniques (think of the telescope and microscope) rather than new developments in theory. Criminologists now have access to new observational techniques in the form of DNA and neuroimaging data. “Never before has the sublime interplay between nature and nurture been available for scientific discovery” (DeLisi, 2009, p. 266), as it is today. The strength of biosocial approaches is that they take advantage of these new observational techniques and in their ability to incorporate biological concepts and findings that have been derived from these sophisticated physical measures into their theories. The main stumbling block is that such studies are more difficult to do and far more expensive than the typi- cal social science study. If we want genetic information, we cannot simply go to the nearest high school and survey a few hundred students. Behavior genetic studies require comparing samples consisting of pairs of identical and fraternal twins and/or adoptees, and these are difficult to come by. However, new technologies have allowed us to go straight to the DNA, thus eliminating this need, but genotyping costs about $10 per individual. Theory Key Concepts Strengths Weaknesses Neuroscience Perspective Whatever its origin, all stimuli are channeled through the brain before given expression in behavior. The development of the brain is strongly influenced by early environmental experiences, especially those involving nurturance and attachment. Shows how environmental experiences are physically “captured” by the brain. Emphasizes the importance of nurturing for optimal development of the brain. Uses sophisticated technology and provides “harder” evidence. High cost of neuroimaging studies. Studies difficult and expensive to conduct but are getting cheaper all the time. The “hardness” of the data may lead us to accept findings too uncritically. Reward Dominance Theory Behavioral activating (BAS) and behavioral inhibiting system (BIS) are dopamine and serotonin driven, respectively. Among criminals the BAS tends to be dominant over the BIS. This BIS/BAS imbalance can lead to addiction to many things, including crime. Explains why low serotonin is related to offending (low serotonin = low self-control). Explains why criminality persistent in some offenders, because they develop a taste for the “thrill of it all.” The neurological underpinnings of the BAS and BIS have been difficult to precisely identify. Nevertheless, it is a model used in many disciplines interested in human behavior. Prefrontal Dysfunction Theory Frontal lobes control long-term planning and temper emotions and their expressions. Criminals have frontal lobes that fail to function the way they do in most people, especially in terms of inhibiting actions that harm others. Explains why moral reasoning is inversely related to involvement in persistent criminality. Explains why criminality has been linked to frontal lobe damage and to abnormal brain waves. Dysfunction of the prefrontal lobes remains difficult to measure, even with fMRI scans. Same sampling difficulties noted for the neurosciences in general. Table 8.1 (Continued)
144 CRIMINOLOGY: THE ESSENTIALS self-control and irritability, but there is always the temptation to treat everyone the same regardless of their serotonin levels. One of the greatest successes of biosocial science was its pivotal role in the United States Supreme Court’s outlawing of the juvenile death penalty. In writing the majority opinion in Roper v. Simmons (2005), Justice Anthony Kennedy noted the neurobiological evidence for the physical immaturity of the adolescent brain, which was brought to the Court’s attention by the American Medical and Psychological Associations (Walsh & Hemmens, 2011). Thus, the biosocial approach can serve to advance arguments both for preven- tion rather than punishment and for punishments that takes into consideration valid physically identifiable differences among people. Matt Robinson (2009), a sociologist who has spent much of his career researching crime prevention, states that [s]ince biosocial criminology meaningfully integrates perspective and theories from the biological and social sciences, the approach offers much hope in the area of crime prevention. At the very least, biosocial crime prevention should be far more effective than those strategies currently utilized. (p. 243) Biosocial studies provide information about both environmental and biological risk factors and, as such, are “more likely to refine social policies by better specification of environmental factors than to divert funds from environmental crime prevention strategies” (Morley & Hall, 2003). In other words, they will enable us to better pinpoint environmental factors that may prove fruitful in our crime prevention efforts.
S U M M A R Y
- Behavior geneticists study the genetic underpinning of traits and characteristics in populations by cal- culating heritability coefficients. There are no genes “for” any kind of complex human behavior; genes simply bias trait values in one direction or another. This view is respectful of human dignity in that it implies self-determinism because our genes are our genes.
- Gene–environment interaction tells us that the impact an environmental situation (e.g., living in a crime-ridden neighborhood) has on us depends on who we are, and gene–environment correlation tells us that who we are is a product of our unique genotype and the environments we find ourselves in.
- Genes have practically no influence on juvenile delinquency, probably because of the high base rate of delinquency; i.e., almost all males commit some acts of delinquency, and thus there is little difference in behavior to be explained by either genes or environment. There are genetic effects for chronic and seri- ous delinquents, but these few individuals tend to get “lost” in studies that combine them with those who limit their offending to adolescence. Adult criminality is much more influenced by genes. One of the reasons that we find only modest genetic effects in criminality when the traits that underlie it are strongly influenced by genes is that parents may have control over their children’s behavior but little or none over their underlying traits.
- Evolutionary psychology focuses on why we have the traits we do, and is more interested in their univer- sality than in their variability. Crime is viewed as a normal but regrettable response to environmental conditions. By this it is meant that many human adaptations forged by natural selection in response to survival and reproductive pressures are easily co-opted to serve morally wrong purposes.
Chapter 8. Biosocial Approaches 145
- In common with all sexually producing species, humans are preeminently concerned with our own sur- vival and reproductive success. The traits designed to assist males in their mating efforts include many that can also assist them to secure other resources illegitimately; in contrast, traits designed to assist females in their parenting efforts are conducive to prosocial behavior. Mating vs. parenting effort is not an either/or thing; males and females engage in both at various times in their lives. It is just that mating effort is more typical of males, and parenting effort is more typical of females.
- Socially cooperating species create niches that cheats can exploit to their advantage by signaling coop- eration but then defaulting. Cheating is a rational strategy in the short term, but invites retaliation in the long term. This is why chronic criminals rarely have successful relationships with others and why they typically die financially destitute.
- Neuroscience tells us that genes have surrendered control of human behavior to the brain. Following genetic wiring to jump-start the process, the brain literally wires itself in response to environmental input. The “softwiring” of our brains is an electrochemical process that depends on the frequency and intensity of early experiences. Adverse experiences can literally physically organize the brain so that we experience the world negatively, which is why nurturing, love, and attachment are so important to the healthy development of humans.
- Reward dominance theory informs us that the brain regulates our behavior through the BIS and BAS systems (underlain by serotonin and dopamine neurotransmitters, respectively). In most people the BAS and BIS are balanced, but criminals tend to have either an overactive BAS or an underactive BIS. This means that their behavior is dominated by reward cues and relatively unaffected by punishment cues.
- Prefrontal dysfunction theory posits that the brain’s prefrontal cortex (PFC) is vital to the so-called executive functions such as planning and modulating emotions. If the PFC is damaged in any way, the individual is deficient in these executive functions and tends to be impulsive.
D I S C U S S I O N Q U E S T I O N S
- If it could be shown with high scientific confidence that some young children inherit genes that put them at 85% risk for developing antisocial proclivities, what do you think should be done? Should their parents be warned to be especially vigilant and to seek early treatment for their children, or would such a warn- ing tend to stigmatize children? What are the costs and benefits of each option?
- We know that males, especially young males, are more likely to perpetrate and be victimized by violent crimes. Provide a plausible evolutionary explanation for this.
- How might reward dominance theory add strength and coherence to low self-control theory?
- Explain why the traits underlying mating versus parenting effort are related to crime.
U S E F U L W E B S I T E S
Anatomy of the Brain. www.neuroguide.com/index.html Behavioral Genetics—Human Genome Project. www.ornl.gov/sci/techresources/Human_Genome/elsi/ behavior.shtml
