Crime Case Studies

Aim: To compare the brain activity of murderers and non-murderers. 

Method: An experiment comparing two levels of the IV using a group of murderers and a control group in matched participants design. The DV was the areas of the brain activity during a controlled task measured using a PET scan. 

Results: Murderers had less brain activity in the prefrontal cortex and corpus callosum than non-murderers and differences in left side and right side activation in the amygdala, temporal lobe, hippocampus, and thalamus. 

Conclusion: Differences in brain activation areas such as the prefrontal cortex and limbic system may predispose criminals to violence. Biological explanation for crime? 

Brain scanning is valid and reliable= scientific technology, Large sample

Scans have to be interpreted, lowered reliability. Generalisability, limited range of criminals  (only murderers), informed consent? Right to withdraw? 

Aim: To find out whether FPE are emotionally affected by case details and whether this emotional context biases their judgements.

Method: 70 FPE volunteered for experiment in which they were given a latent mark on a £50 and a set of comparison prints to match. They were given either low or high emotion case information in a independent measures design. Their reported feelings about the case information and whether this affected their decision about the fingermark match were measured.

Results: 52% of the 30 analysts who had the high emotion case info felt affected by it compared to 6% in the low emotion condition. However, no significant difference was found between the decisions by participants in the two emotional contexts nor in their willingness to present the mark in court (equally confident). Conclusion: Emotional context affects experts feelings but not their decision about fingermark matches. 

High ecological validity- based on real life, no deception, ethical, protected from harm. confidentiality. 

Low ecological validity- artifical, knew it wasn't real+no conversations about case allowed. 

Method: A review, structured around the effectiveness of various components of the cognitive interview, the relationship between the CI and other interviewing methods, different measures of memory performance and the effect this has on research findings and interviewer variables and the effect of training quality on interview performance. 

Results: Context reinstatement is the most effective component of CI. Comparisons between CI and SPI are now dated and suggest that future research should compare the two. Problems associated with differing measures of memory and factors such as the quality and length of the training given to interviewers. 

Lab studies- control extraneous variables, Field studies high ecological validity 

Lab studies lack ecological validity, if people are shown fake events, ensure that they do not cause distress. 

Aim: To test if a Birmingham accented suspect would produce stronger attributions of guilt than a standard accented suspect. And if race or type of crime also influenced this. 

Method: An experimental design with three variables (accent, race, type of crime). 119 undergraduates listened to one audio recording of a fake police transcript then rated the likely guilt of the suspect on a 7 point scale. 

Results: Birmingham accent was rated as the most likely to be guilty. Birmingham accent, black, blue collar crime had significantly higher ratings of guilt than other conditions. Conclusion: Accent has a significant effect on judgements of guilt and innocence. 

Control of many confounding variables, make sure IV is thing being tested, deliberating in groups- mock jury. Protected from distress, ethical. 

Ecological validity- not a real jury, low realism, only psychology stydents- unrepresentative. Socially sensitive. 

Aim: Explore the relationship between low level crime and serious offences within communities.

Method: The authors considered the Newark Foot Patrol experiment as a case study, and engaged in participant observations of police officers in communites. 

Results: Increased foot patrols resulted in better community relations and lowered residents fear of crime. Fear of crime and poor relations with police can lead to a lack of responsibility and personal involvement in community affairs. Just as a single broken window when ignored can lead to many more being destroyed, serious crime was theorised to emerge from increasing levels of disorder and antisocial behaviour. 

Conclusion: The theory of broken windows can help explain the link between public disorder and serious crime. Lowered crime rates. CCTV, privacy? Reporter Bias, long term effects? Extraneous variables, Costs of crime prevention strategies. Some groups more vunverable to zero tolerance policies. Alienation of police. 

Aim: The aim of the study was to investigate the effect of being given the roles of prisoner and guard.

Method: 24 white middle class male college students randomly assinged the role of prisoner or guard. Mock prison at Stanford Uni. Given uniforms, told study would last 2 weeks. Participants observed and their behaviour was recorded by the experimenters. 

Results: Both prisoners and guards adopted their roles quickly and began to show pathological behaviour. Guards were hostile and aggressive, prisoners became extremely distressed. Ended after 6 days due to condtions. Conclusion: Situational factors offer a better explanation than dispositional factors for the social roles taken on by P's. Important impliocations to how prison guards are trained. 

Balanced control of some variables with some ecological validity. True to life- arrested in their homes. Generalisability. Sample limited- generalisability, demand characteristics, absence of some aspects of prison life. Major ethical concerns, imprisonment has largely negative impact. Can affect mental health.