Human behavior is a complex phenomenon. Between psychology, sociology, and biology, there is still no definitive answer as to why humans behave the way that they do. Taking this one step further, criminal behavior is just as inexplicable. Controversy continues to surround the nature vs. nurture debate that seeks to find whether behaviors are determined by genetics or environmental influences. It is difficult to know with confidence the extent to which they each contribute to human behaviors and it is almost impossible to disregard either biology or sociology when attempting to explain it.
Biosocial criminology argues that biology is influenced by environmental factors. It also argues that it is biological factors that make an individual more or less susceptible to criminal behaviors. When combining biological concepts to sociological theories, it provides a better understanding of how the two interact to produce certain behaviors, and criminal behaviors at that. There is no clear answer as to whether or not crime is biologically determined. However, there are many studies that help to break this down and understand the many moving parts of the phenomenon. While there is no research to support the idea behind a specified crime gene, genetics do interact with the environment to produce certain traits that are strongly correlated with criminal behaviors.
In 1964, Hans Eysenck was one of the first psychologists to explore the idea of nonsocial influences on criminal behaviors. His initial research surrounded neurobiological influences on criminality through the study of twin data. Through his research, Eysenck was able to determine that there are higher incidences of criminal behaviors in identical twins (77%) as opposed to fraternal twins (12%).
This dramatic difference suggests that there is a genetic influence on criminal behaviors – the closer in genetic makeup the siblings were, the more likely they were to both be involved in criminal activity. While it was too early on in science at the time to determine exactly what the measure of genetic influence was, his conclusions exhibited a consistent correlation between criminal behavior and genetics (Fox, 2017). Two years later, in 1966, Ronald Akers and Robert Burgess used the Social Learning Theory (SLT) to create and explain a Theory of Criminal Behavior. The two criminologists identified four SLT concepts to explain how biology must play a role in criminal behaviors.
The first concept noted was differential association, which assumes that associating oneself with criminals makes an individual more susceptible to engaging in criminal behaviors themselves (Fox, 2017). This aspect of the Social Learning Theory is one of the most common and studied concepts in all criminology findings. This is a popular sociological explanation for behaviors since individuals are greatly influenced by their peers. The second concept is definitions, which is how people determine or qualify certain behaviors as right or wrong. Creating standards for behavior allows people to define what behaviors are acceptable, and which behaviors are unacceptable (Fox, 2017).
In this case, if someone is able to justify a criminal act as acceptable, they are more likely to commit the crime. For example, someone might justify karma as an excuse as to why murdering someone might be permissible, while someone else may consider that completely immoral. The third concept is differential reinforcement. This is the idea that the likelihood of an individual’s actions is dependent upon past and potential punishments and rewards (Fox, 2017). If someone has stolen and gotten away with it every single time, they will most likely continue to steal because they have reaped the benefits of whatever they stole without facing consequences. However, if someone attempts to steal something once and gets arrested the first time, they are less likely to attempt to steal again because they were punished for it in the past.
The third and final concept is imitation, which is whether or not an individual will mimic someone else’s behaviors based on their outcomes and consequences. If someone is found to be successful in criminal activity and proceed without consequence, their actions are more likely to be imitated by their counterparts (Fox, 2017). Despite their validity, these concepts cannot be generalized to everyone.
There are individuals who are more likely to fall into peer pressure or imitate criminal behaviors than others, and for this reason it was necessary for Akers and Burgess to account for genetic makeup. It is also important to note that while genetic factors do influence criminal behaviors, they are certainly not the sole determinant. In fact, biology plays a dominant role in determining how an individual will react to their environment as opposed to biology directly controlling or influencing an individual’s behaviors (Fox, 2017). For the past twenty or so years, the General Theory of Crime has become one of the most widely debated and challenged theories in criminology.
This theory was developed by criminologists Travis Hirschi and Michael Gottfredson and can also be referred to as the Self-Control Theory of Crime, which was created in 1990. The General Theory of Crime argues that low self-control and criminal behavior are strongly correlated. According to this theory, an individual’s early life and family environment influence self-control. Hirschi and Gottfredson define self-control as, “the ability to forego immediate or near-term pleasures that have some negative consequences and the ability to act in favor of longer-term interests” (Gottfredson, 2017). While these criminologists believe that self-control is a learned trait, there have been many studies that link this trait to genetics, specifically the MAOA gene.
Neurocriminology is a relatively new study that focuses solely on unraveling the complex relationship between biology and behavior. Instead of applying sociological theories to help understand the relationship, neurocriminology applies techniques and principles from neuroscience to help predict and ultimately prevent crime (Glenn & Raine, 2014). This science was started when brain imaging began to study the brains of violent criminals compared to non-violent people with no criminal history (Raine, 2013).
Adriane Raine is one of the pioneers of neurocriminology as he has continued to dig deeper to find clearer biological connections to criminal behaviors. Raine believes that, “’Just as there’s a biological basis for schizophrenia and anxiety disorders and depression, I’m saying here there’s a biological basis also to recidivistic violent offending’” (2013). Raine believes that these findings would transform preventative strategies as well as rehabilitation.
This is because if society starts to view criminals as helpless victims of predisposed tendencies instead of evil people, they will be more susceptible to treat them instead of solely punish them (Raine, 2013). If research is able to prove that violent, criminal, and anti-social behaviors are truly based on genetics, should we hold the individuals with these genes fully responsible for the way that they behave? Raine often refers to his own early life where he was on a path to becoming a criminal and links those behaviors to his low resting heart rate, brain scans that mimic a serial killers, and lack of nutrition as a child (Raine, 2013). He is intrigued and driven to find out how he was able to turn his situation around and avoid disaster. There are numerous studies that find connections between certain behavioral traits, genetic components, and crime (Glenn & Raine, 2014).
Notable studies when discussing neurocriminology are twin studies. Consistent with Eysenck’s findings, twins who are adopted have similar propensities to crime over their lifetime. Adoption studies are a great resource because they allow researchers to separate genetics from environmental factors in order to prove heritability. More recently, research has been focused on locating a specific gene that makes individuals more at risk to engage in criminal behaviors. It is important to note that the environment plays an influential part in all genetic variations and is the reason why individuals respond differently to situations and stimuli. Research has proven that the environment influences how genes are expressed (Glenn & Raine, 2014).
One of the most common misconceptions when linking biology to criminal behavior is that there exists a ‘crime gene’. When considering biology and crime, many believe that there is a gene that results in criminal behaviors in some of us and not in others. While this idea is not entirely false, it is widely misinterpreted. There is no ‘crime gene’. What there are, however, are certain genes that respond and interact to an individual’s environment, making them more or less likely to portray certain traits. The notion that both biology and environment influence an individual can be referred to as a biosocial perspective, which is broken up into two parts. The first is part is biological influence in which research indicates up to 60% of antisocial and criminal behavior is inheritable.
The second part of this perspective is the social influence that explains up to 50% of variance in criminal behaviors (Fox, 2017). One of the very first risk factors for criminal behavior can be identified during the prenatal and perinatal periods. Health issues in early pregnancy were found to be a determinant of antisocial and aggressive traits, which are linked to criminal behaviors. In Denmark, a study found that birth complications and maternal rejection in a child’s first year have been linked to violent criminal offending in adulthood (Glenn & Raine, 2014). The same findings have been consistent in the United States, Canada, Sweden and Finland. Other studies have shown links between early health complications and aggression, delinquency and low self-control (Glenn & Raine, 2014). While genes do not cause behaviors, they do interact with the environment to produce certain traits and tendencies.
People with low self-control lack diligence, can be impulsive, thrill-seekers who are usually self-centered. Low self-control is known to be a result of ineffective rearing by a child’s parents. While self-control is a large determinant of criminal behavior, several studies have utilized a gene named the MAOA gene to successfully prove its connection to behavior (Gonzalez-Tapia & Obsuth, 2015). This gene has been referred to by many as the “warrior gene” as a result of its links to aggression and violent behaviors.
The MAOA gene is an enzyme that is located on the X chromosome and is directly related to dopaminergic and serotonergic systems, which regulate serotonin and dopamine (Gonzalez-Tapia & Obsuth, 2015). These chemical messengers control reward and punishment sensitivities as well as thresholds for pleasure and displeasure (Gonzalez-Tapia & Obsuth, 2015). But what is the connection between the MAOA gene, these systems, and criminal behavior?
The tie to biology and criminal behavior is that these systems vary within individuals. This variation leads to some people to be less sensitive to punishments and displeasure and subsequently making them more prone to engage in criminal behavior since they are not as affected as others by current and future consequences (Watts & McNulty, 2016). In a recent study, criminal behavior, low self-control and the MAOA gene were measured against one another in order to help explain the relationship between genotype and behavior.
The conclusion of the study was that the MAOA gene and the DAT1 dopamine transporter do, in fact, impact self-control and criminal engagement. The reasoning behind this is that these two biological factors interact with environmental triggers, such as self-control, which is highly correlated with criminal behavior. However, the MAOA gene only explains a small proportion of why antisocial behaviors arise, and the rest can be explained by environmental factors. Therefore, since environmental factors play a role, biology does not necessarily determine crime, instead it influences it.