Criminals are not born. The basic definition of the word criminal is someone who commits offensive behavior within society (Harrower, 2001). The crime can range from petty theft to murder. Criminals are not born. It is the discussion of this essay that will explore theories that attempt to explain criminal behavior. Psychologists have proposed various theories and reasons as to why individuals commit crimes. These theories represent part of the classic psychological debate, nature versus nurture. Are individuals predisposed to becoming criminals or are they created by their environment. There are various theories in the biological explanation of why individuals commit criminal behavior, including: genetic theory, hereditary theory, psychosis, and brain damage theory. In the next paragraphs, examples of each will be presented. The first theory to explore is the hereditary theory, which stems from Cesare Lombroso (1876), father of criminology, (Feldman, 1993), whose studies were carried out by morphology. Lombroso attempted to show a relationship between criminal behavior and physical characteristics. Lombrosco suggested that an individual was predisposed to becoming a criminal, due to internal or innate characteristics, rather than environmental factors. Lombroso observed criminals and non-criminals through their physical abnormalities, such as measurements and physical examinations. He concluded that most of the prisoners had the same physical abnormalities, which supported his assertion that they were the same type of criminal. Abnormal features may have included: large jaws, high cheekbones, large ears, and extra toes and fingers. Lombroso claimed that these physical "stigmas" indica...... middle of article...... Psychology in Practice: Crime, London, HodderJOSEPH, J (2001), Is Crime in the Genes : a critical review of twins and studies on the adoption of criminality and antisocial behavior.LEO, J and CASTRONOVO,V (1985), Behavior; Are criminals born, not made? [online], available at: http://www.time.com/time/magazine/article/0,9171,960148,00.html#ixzz1ayjFrn6N[accessed October 16, 2011] MCGUIRE, J (2004) Understanding Psychology and Crime; Perspectives on Theory and Action, New York.PENNINGTON, D (2002), Introducing Psychology: Approaches, Topics and Methods, London, Hodder ArnoldTANNENBAUN, B, (2007),Professors link criminal behavior to genetics [online], available at: http://thedp.com/index.php/article/2007/11/profs_link_criminal_behavior_to_genetics [accessed October 16, 2011]. http://www.docstoc.com/docs/41182390/Explanations-of-Criminal- behavior