Forensic Psychology

• The top-down approach to offender profiling (used by the FBI) has 4 stages:

  • data assimilation
  • crime scene classification (organised/disorganised)
  • crime reconstruction
  • profile generation
• In the top-down approach crime scene characteristics are used to identify the type of offender. Organised offenders leave little to no evidence and usually the victim is a stranger; they are likely intelligent and socially competent. Disorganised types usually know their victim and leave behind a sloppy crime scene; they are likely immature, unintelligent and sexually inhibited.
• The offender types in the top-down approach are based on interviews of 36 American sex offender done by Douglas and Hazelwood in 1980. Of the 36, about 50% were classified as having superior intelligence. This evidence provides limited support as it is only relevant to one type of crime.
• In practice, the top down approach has been found to have limited effectiveness. According to Holmes (1998) it contributed to arrest in only 17% of the cases it was used in.
• The theory behind the top-down approach is deterministic as it assumes offender behaviour is determined by personality. Alison et al (2002) found evidence to suggest that offending behaviour is not merely shaped by personality but a complex interaction of many factors.
• The bottom-up approach looks at 3 main factors in terms of offender profiling:

  • Significance of time and place
  • Interpersonal coherence (consistency of behaviour when offending and in everyday life)
  • Forensic awareness ('covering their tracks')
• The bottom-up approach comprises 2 parts. The first is investigative psychology which looks for consistencies in the offenders behvaiour during the crime:

  • It starts with details then creates a bigger picture.
  • It is a data driven approach that looks at similar crimes
  • It aims to make predictions about the characteristics of an offender.
• The second part of the bottom-up approach is geographical profiling. This uses 'circle theory' which suggests that crimes are committed in a circular radius to the offender's home. This is done with a computer system called Criminal Geographic Targeting.
• Within geographical profiling there are 2 types of offenders:

  • Commuters who travel to commit their crimes; a circle can still be drawn but it is far away from their home location.
  • Marauders who commit crimes in their own neighbourhood.
• The case study of the Railway Rapist provides support for the bottum-up approach. Canter was able to identify where the killer lived and that he was unhappily married and childless (overall correct on 13/17 points). He was able to use this to find a correct match with John Duffy.
• The case of Rachel Nickell does not provide support for the bottom-up approach. The police wrongfully accused a man who walked his dog in the area she was murdered. When they later found the real killer they discovered that he was several inches taller than the profile suggested.
• Investigative psychology has limited applications as it is only used for serious and violent crimes.
• Canter et al found that 85% of serial murderers lived within the circle encompassing their offences. However Snook et al examined 53 serial killers in Germany and found that 63% of them lived within 6 miles of where the bodies were found. This variance suggesrs there are still elements of individual differences.
• The Atavistic Form theory is a historical biological explanation of criminality (don't use as main basis for a 16 mark q). It was proposed by Lombroso in the 19th century. He suggested that there was an 'atavistic' class of people prone to criminality who were at a more primitive stage of evolution. The physical characteristics include a protruding jaw, drooping eyes and large ears.
• One biological explanation of offending behaviour is genetics. The MAOA gene codes for the production of an enzyme that is responsible for clearing serotonin from synapses in the brain. In criminals this gene has low activation so the enzyme does not clear serotonin and their brain is bathed in it which makes them numb to it. This leads to unregulated mood and therefore aggression. Studies of violent criminals have found they often have a defect in the MAOA gene.
• There is support for the genetic explanation from research done on mice. Cases et al disabled the MAOA gene in mice and found that levels of serotonin and dopamine were altered and aggression increased. This research has high internal validity because it was done in a lab with high levels of control. However it cannot be fully extrapolated to humans as we are influenced by other factors like morals and fear of punishment.
• There is support for the genetic explanation from adoption studies. Crowe et al (1972) compared adopted children with/without criminal mothers. 50% of those with a criminal mother also had one by the age of 18 compared to 5% of the control group. However there is also support for a diathesis-stress model meaning both genetics and environment determine whether someone will become an offender.
• The neural explanation for offending behaviour suggests there is a link between abnormalities in areas of the brain and aggression. The amygdala is in the centre of the brain and is responsible for anger, fear and anxiety so a criminal's amygdala may be damaged. The prefrontal cortex is the cortical component of the anger response. If it is damaged someone may seek instant gratification and lose their impulse control.
• Charles Whitman suffered from increased anger and hostility, lack of sleep and taking excessive notes. Although he was aware it was immoral, he ended up killing his wife, mother and several strangers. It was found in a post-mortem that he had a tumour pressing on his amygdala. However there were other factors in his life that may have contributed to his violence: time spent in the military and a 'brutal, domineering and extremely demanding father'.
• There is also support for the neural approach from controlled research. Raine et al did PET scans on 41 murderers and 41 control participants. The murderers generally had less activity in the frontal lobe and less activity on the left side of the amygdala.
• The neural biological explanation is socially sensitive. Raine implied that those with the aforementioned brain abnormalities should be screened and have 'something done about it' i.e. imprisonment or genetics. This is unethical as it treats innocent people as criminals.
• The neural explanation is highly deterministic which is problematic as it suggests that people are not responsible for their behaviour and cannot be held accountable.
• Eysenck's theory of criminal personality suggests that personality is biologically based and can be assessed by 3 personality traits: extraversion, neuroticism and psychoticism. These are assessed through the Eysenck personality inventory.
• Extraversion is the need for environmental stimulation determined by level of arousal in the CNS and ANS. Neuroticism is the stability of someone's personality. Psychoticism is the degree to which someone is anti-social, aggressive and uncaring.
• Eysenck and his wife assessed 2070 male prisoners who were compared with a control group of 2422 males. On measures of E, N and P, prisoners scored higher than the control. However prisoners may have changed their answers to appear tougher
• Eysenck's theory is based on measuring personality however personality is not fixed and can change depending on when people do the questionnaire.
• Eysenck's theory has positive applications for preventing crime by modifying the socialisation of high-risk individuals.
• A cognitive (psychological) explanation for offending behaviour is level of moral reasoning. Kohlberg's theory suggested that criminals operate at a lower level of moral reasoning than normal people. There are three levels of moral reasoning, preconventional (children) conventional (adolescents) and postconventional (adults).
• An example of the stages within the levels of moral reasoning are stage 1 - acting to avoid punishment and stage 2 - acting to further one's interests. Heinz's dilemma is used to assess Kohlberg's stages of moral reasoning.
• Palmer and Hollin compared moral reasoning between non-offenders with 126 convicted offenders using the social moral reasoning scale. Offenders showed less mature moral reasoning than the non-offenders. This could be because their childhood lacked moral role-play opportunities.
• Carol Gilligan criticised Kohlberg's theory by proposing that men and women reason differently about morality (morality of caring for women and morality of justice for men). Shaffer et Al also argued that emotion plays a central role in morality
• Another psychological explanation of offending behaviour is cognitive distortions. They are patterns of negative and exaggerated thought that reinforce maladaptive behaviour.
• One kind of cognitive distortion is hostile attribution bias, which is interpreting the actions of others as hostile when they are not. This leads to aggressive behaviour.
• Another kind of cognitive distortion is minimalistic, which is playing down the severity of the circumstances you are in and minimising the consequences of your actions. Offenders use this to reduce their guilt and even blame the victim.
• Research into hostile attribution bias: 55 violent offenders were shown images of ambiguous facial expressions. Offenders were more likely to perceive them as angry. However there are issues with ecological validity.
• Research into minimalisation: amongst 26 convicted rapists, half denied they had committed an offence at all and 40% minimised the harm they had caused the victim. However this only applies to one type of crime.
• The theory of cognitive distortions is useful in treating criminal behaviour by using CBT in prisons. However this may be problematic as prisoners might not be highly motivated.
• Sutherland's psychological explanation Differential Association Theory states that criminal activity is due to environment and socialisation. Interaction (operant conditioning) and observations (social learning theory) are how criminals learn deviance.
• In Differential association theory, criminals learn through family members then peer group. The frequency, meaningfulness and length of interaction are significant.
• Two factors are learned in differential association: attitudes towards crime and the skills required for the criminal act itself.