Deviant behaviours have always been identified all through history and efforts to understand their root led to the emergence of numerous theories from the medieval era to date. In the long past biology was an explanation for such behaviours; for example, in the ancient criminal justice system, during a dispute, the uglier suspect would be found guilty (Wilson & Hernstein 1985). This approach differs from a modern approach where genetics, psychology and social factors are more acceptable explanations to deviant behaviours.

Lambroso (1876) came up with a theory while working in prisons that criminals possess certain physical features such as low foreheads, protruding jaws and cheekbones, hairy bodies, and usually long arms. In addition, he argued that compulsive, primitive, and organic abnormalities were explanations for criminal behaviour. In other words, Lambroso believed that the biological make up of an individual was responsible for their criminal behaviour. This theory suggests that people with certain biological features would always become deviant. Lambroso's theory was based on his personal beliefs in interpreting his observation of prisoners in Italian prisons. Additionally, his findings were not a result of scientific research study. In support for Lambroso (1912), Taylor et al., (1973) argued that biology was an explanation for criminal behaviour. They further argued that criminals are primitive and inferior animals. Taylor et al. (1973) actually believed that criminals were inferior animals who have for some reason not fully evolved from their primate forms. Hooten, (1939) also laid support for biological explanation for deviancy, and argued that criminals are deteriorated inferior human organism, and that criminal propensities were based on the shapes of their bodies such as height, weight, nose, as well as narrow foreheads and elongated and pinched noses for sexual criminals.

In genetics the X is known as the female chromosome while the Y is the male chromosome. A female would carry an XX set of chromosomes one from each donating parent, while a male would carry XY chromosomes, again, one from each donating parent. In rare cases there are individuals who have inherited an extra male chromosome which experts claim are responsible for aggressive behaviours that result to violent crimes. In the sixties, genetics known as XYY was claimed to have link with violence and aggressive behaviour, and was used to explain deviant behaviour. Jarvik (1972) argued that the extra Y chromosome had a characteristic of forcefulness and aggressive predispositions due to rareness in tallness and masculinity. Guo, Cai, Guo, Wang, & Harris (2010) claimed that numerous genes linked with the transmission and reception of the neurotransmitter dopamine such as the DATI, DRD2, and SRD4 are linked to a number of antisocial behaviour.

Implications

However, biological explanations to deviant behaviour becomes problematic as facial, body, and physical features are used to explain such behaviour, whereas numerous law abiding people can possess these features. According to Hooten's (1939) explanation, people with narrow foreheads, elongated and pinched nose are sexual criminal. This could be true by chance and may not have any generalization effect. This biological concept of criminality can be a tool for discrimination, racism, unlawful labeling, and more if not well managed.

In the past biology was a tool for racism and discrimination. Historically, a number of these theories had racial undertones; for example, the biological and genetic tools were used to justify and support diverse actions such as aggression, violence, oppressive policies, or even hate behaviour carried out against people of certain race, ethnicity, and background by some governments, groups, or organisations. Looking at the descriptions of dangerous criminals according to many of the previous theorists, it is evident that their concept of criminality was ethnocentric as their description of criminality were in most cases based on feature of races and ethnicity different from themselves.

If the biology of an individual is responsible for their aggressive and criminal behaviour, it then sends a negative message to criminals that they are not responsible for their behaviour as they have no control of their biological makeup. It can be argued that the biology of a person is not what is responsible for criminality, however, biology can play a part in facilitating aggressive behaviour. It is necessary to understand that aggression, violence, and criminality can be exerted by all shapes and sizes, any race or ethnic group. It is unscientific, biased, and naive to sign post certain group as criminals based on their biological make up alone . More specifically, if all human traits are determined by their biology and genes, then there appears to be little or no room for free will.

Deviant behaviour According to Durkheim (1960) is the failure to conform or comply with given rules or norms of the group in question. In other words, the group’s norms, and moral code in judging the behaviour must be recognized in order to consider the behaviour as normal or deviant. Ellwood (1912) argued that crime is a matter of habit, and that people’s habits are adjusted to fit in with one another for the welfare of their group, and that deviance occurs when a person’s habit becomes maladjusted compared to that of the group. Sutherland (1934) claimed that people acquire various elements critical to deviance via group association and that the norms and values of deviant culture, techniques and ways of legitimizing their deviant behaviours. In support for social explanations for deviant behaviour, Gottfredson and Hirschi (1990) argued that deviant people have low self-control, which is a result of poor childhood socialization. They further claimed that the behaviour endures through life regardless of factors such as criminal justice system.

Implication

This explanation to criminality argues that people are deviant or criminals not because they are criminal by nature but because they fail to comply to the norms of the group or society. In other words, in the case where a member of the group genuinely believes that the group's norms are for example immoral, oppressive, or not representing the interest of members or society, and as a result deviates from the norms, the individual will be tagged a criminal or deviant. How would the person's behaviour be explained in terms of deviancy or criminality? In other words, the group can sometimes get it wrong. That does not mean that the individual who gets it right is a deviant or a criminal.

It is true that what is considered a criminal behaviour in one society or culture is not always necessarily deviant across society and cultures. This sort of theory can be a tool for social control where people are expected to follow the rules placed by the group, society, or country. The original idea is obedience and conformity to the group. It can be argued from the perspective of 'failure to conform' that what is right or wrong is based on the group's belief system as opposed to that of the individual. When members of the group or society begins to deviate from those beliefs, they become classed as deviants. Therefore, explaining deviancy from this angle would mean that the societal system is ultimate, making challengers of authorities and the system to be deviants or criminals. This includes protesters, opposition groups as well as pressure groups.