Presentation on theme: "Theories of Crime. Lombroso Lombroso in 1876 argued that the criminal is a separate species, a species that is between modern and primitive humans. He."— Presentation transcript:
Theories of Crime
Lombroso Lombroso in 1876 argued that the criminal is a separate species, a species that is between modern and primitive humans. He argued that the physical shape of the head and face determined the "born criminal".
William Sheldon believed that people could be classified into three body shapes, which correspond with three different personality types. 1. endomorphic (fat and soft) tend to be sociable and relaxed. 2. ectomorphic (thin and fragile) are introverted and restrained 3. mesomorphic (muscular and hard) tend to be aggressive and adventurous. Sheldon, using a correlational study, found that many convicts were mesomorphic, and they were least likely to be ectomorphic (Sheldon et al 1949).
Genetic - XYY Normal Male
Genetic - XYY XYY Male
Genetic - XYY XYY Male Jacobs et al (1965) suggested that men with the XYY syndrome were more aggressive than normal 'XY' men. XYY men are over- represented in the prison population. There are 15 sufferers per 1,000 in prisons and 1 per 1000 in the general population.
Neurophysiological Raine 1994 used PET scans to study the living brains of impulsive killers. Damage was found in the pre-frontal cortex, which controls impulsive behaviour. The task used involved sustained attention. It involved watching a screen for 32 minutes and responding every time a 0 appeared. Impulsive individuals also missed many of the 0s. Oddly enough, pre-frontal under arousal has also been found in politicians! Raine
Neurophysiological PET Scanner
Neurophysiological PET Scan
ADHD Another suggestion is that certain individuals, as a result of genetic predisposition or brain damage at birth, suffer from a cluster of symptoms which render them incapable of moral control and because of cortical under arousal, they are constantly seeking stimulation.
Neurochemical The brains chemistry can be influenced by diet, for example, food additives, pollution or hypoglycaemia (low blood sugar levels associated with forms of diabetes). Dawn Stanton attacked her husband with a knife when hypoglycaemic. But not all diabetics without insulin act criminally.
Neurochemical Individuals who take large amounts of steroids can become extremely violent (known as "roid rage"). Steroids, usually taken to increase muscle growth, also increase testosterone levels. Horace Williams, a body builder, beat a man to death after taking two thousand times the recommended dosage of steroids.
Twin studies An 'MZ apart' study is when two monozygotic children have been brought up apart. If both turn out to be criminals then this would be support for the genetic explanation. The degree of similarity between two twins is known as the concordance rate. This rate can then be compared with dizygotic twins who are brought up together ('DZ together'). Looking at a number of studies the average concordance rate is 55% for MZ twins and 17% for DZ twins (Bartol, 1999).
Evaluation Different studies define criminality in different ways (e.g. traffic violations, military offences, treason during World war 2). Quasi-experimental designs are not so controlled as experimental designs. Age of separation of MZ twins. Misclassification of twins as MZ or DZ.
Evaluation MZ twins look alike and may therefore generate more similar social responses than DZ twins. This means that in addition to sharing the same genes, they may also share an almost identical social environment. MZ twins often have a very close: relationship and may therefore develop similar interests, which might include criminal behaviour.
Evaluation Very small sample size in some studies, because of the inherent difficulties in obtaining access to criminal twins. Variable definitions of criminal behaviour.
adoption studies A retrospective study by Mednick et al (1987) looked at court convictions in a small European country and found 14,000 adoptees amongst them. The criminal records of their biological and adoptive parents were then investigated. Many of the adoptees had criminal biological parents (particularly strong relationship for sons and fathers). There was no relationship in the types of crime committed. Where there was an improvement in social conditions there was a reduction in crime (going against the genetic explanation).
adoption studies Biological parents have criminal record Adoptive parents have criminal record % of sons with criminal record (Mednick 1987) % of sons with criminal record (Bohman, 1995) No Yes No No Yes Yes
Evaluation 1 Age of adoption 2 Amount of contact with biological parents (contamination effect) 3 Adoptive family selected to be similar to biological family. 4 Small sample sizes.
Psychological: Eysenck's Personality theory Extraverts need excitement so they are more likely to seek crime in order to gain excitement. Eysenck proposed that extraverts do not condition easily. Whereas others would learn that crime does not pay through classical and operant conditioning, the extravert would not learn these associations.
Eysencks Personality Theory
Traumatic Experiences Traumatic experiences in early childhood leave their mark on the individual despite the fact that the individual was not aware of these experiences. se/ /Kaleta/InS00Personali tyFreud.htm
Freud and Effect of Family Alexander and Healy (1935) suggested that children need to progress from the pleasure principal (being id dominated and therefore needing instant gratification) to the reality principle (where the ego is dominant). Criminals are those children who do not make this transition. According to Freud the child needs a stable home environment in order to successfully make this transition. Research has supported the fact that most criminals come from unstable homes.
FREUDIAN APPROACH John Bowlby (1946) (see Hodges and Tizard) studied 44 juvenile delinquents and compared them with non-criminal disturbed juveniles. 39% of the delinquents had experienced complete separation from their mothers for six-months or more during the first five years of their lives compared with 5% of the control group.Hodges and Tizard
Problems with Bowlby's research: unrepresentative samples poor matching for control group low reliability in the interviews with participants (Feldmann 1977).
Evidence against Bowlby Koluchova (1976) studied a pair of Czech twins and reported that although they were severely neglected for the first 7 years of their lives they were deemed normal by the time they were 14 after being cared for. Clarke and Clarke (1976) studied children from deprived backgrounds using a longitudinal study and found there were many factors that contributed to the child becoming a criminal, not just whether or not they were maternally deprived.
However (Fred and Rosemary) However, the effects of emotional or sexual abuse can well be believed when we find that 'serial killers' such as Frederick and Rosemary West suffered terribly as children (Wansell 1996).
Child abuse Out of 36 sex murderers interviewed in the USA 42% were found to have been sexually abused as youngsters (Ressler et al 1988). Dietz and Warren (1995) found that 76% of the 41 serial rapists that they interviewed were abused when young. But only about 10% of abused children go on to commit crimes.
BanduraBandura's Social learning theory Bandura (1977) suggests that there are three aspects to motivation: 1. External reinforcement (as in operant theory) 2. Vicarious reinforcement – the observation of other people being rewarded or punished for their behaviour 3. Self-reinforcement – gaining internal satisfaction from an activity, which therefore motivates the individual to behave in a similar way in the future.
Bandura 1976 Observational learning is thought to take place primarily in three contexts: 1. In the family 2. in the prevalent sub culture 3. Through cultural symbols such as television and books.
Learning theory and social learning theories of crime evaluation For The theories are based on carefully conducted empirical research They can help to explain why criminality does, to an extent run in families. Males and females are socialised very differently, with females encouraged not to be aggressive and to conform, males are encouraged to stick up for themselves and be independent.
Learning theory and social learning theories of crime evaluation Against The studies on which these theories are based are conducted in laboratories or other artificial environments in carefully controlled conditions. They therefore lack ecological validity in that they may not be sampling behaviour as it occurs in real life situations.
Learning theory and social learning theories of crime evaluation Against The fact that criminal behaviour tends to run in families is not necessarily due to imitation but may be due to circumstances such as social deprivation, or to genetic propensity to behave in an anti-social way. There are biological differences between men and women, especially hormonal ones, and this, rather than socialisation, may account for differential rates of crime between men and women.
Sutherland (1939) differential association criminal behaviour is learned; the learning is through association with other people; the main part of the learning takes place within close personal groups; the learning includes techniques to carry out certain crimes and also specific attitudes and motives conducive towards committing crime;
Sutherland (1939) differential association the learning experiences differential associations will vary in frequency and importance for each individual; the process of learning criminal behaviour is no different from the learning of any other behaviour.