Forensics

Define: Forensic Psychology

The application of scientific knowledge and methods to help answer legal questions. The intersection of law and psychology.

Define: Offender Profiling

An investigative tool that aids the identification and conviction of an unknown criminal by building a likely identity based on crime scene evidence.

Define: Top-Down Approach

Offender profiling that uses pre-existing knowledge about criminal behaviour and personality. Developed by FBI.

Define: Organised Criminal

A criminal who works in a structured, premeditated way. Evidence the victim was deliberately targeted, little evidence left at scene.

Define: Disorganised Criminal

A criminal who is more likely to have committed the act spontaneously and out of momentary passion. Little evidence of planning, the crime scene reflects the impulsive nature.

Define: FBI Profile

A process of identifying all the psychological characteristics of an individual, forming a general description of the person, based on the analysis of the crimes committed by them.

FBI Profile: 4 steps

1. Data Assimulation

2. Crime Scene Classification

3. Crime Reconstruction

4. Profile Generation

Define: Bottom-up Approach

Analysing the specific details of a crime scene and the offender’s behaviour to build a profile. Based on statistical database.

Define: Modus Operandi

A particular way or method of doing something. An identifying pattern used to identify a criminal.

Define: Investigative Psychology

The application of psychological theories to the crime investigative process.

Define: Smallest Space Analysis

Calculation of spatial consistency in the behaviour of a criminal. The likelihood of MO factors occurring together.

Define: Geographical profiling

Analysing the location of a connected series of crimes to make inferences of a likely operation base. Based on spatial consistency.

Define: Interpersonal Coherence

Analysing the behaviour of an offender can help establish and understand offender behaviour in their day-to-day life.

Define: Spatial Consistency

The assumption that offenders will restrict their work to geographical areas they are familiar with.

Define: Circle Theory

A form of geographical profiling which categorises offenders based on their spatial decision-making offering an insight into the nature of the offence.

Define: Marauder

An offender who operates in an area they are familiar with, and their crimes form a circle around their usual residence.

Define: Commuter

An offender who is likely to have traveled a distance away from their usual residence.

Top-Down Evaluation: Canter et al (2004)

Analysis of 100 US murders suggested evidence of an organised type but no evidence of a disorganised type.

Top-Down Evaluation: Scientific Basis

Canter (2000) - Crime scene evidence is often incomplete and ambiguous.

High ecological Validity

Low population Validity - 36 extreme cases

Based on self-report - social desirability bias or a “screw you” effect

Top-Down Evaluation: Meketa (2017)

Top-down approach had been applied to burglary leading to 85% rise in solved cases.

Bottom-Up Evaluation: Railway Rapist (Profile)

Canter’s profile of the railway rapist was surprisingly accurate and led to conviction of John Duffy.

Bottom-Up Evaluation: Railway Rapist (support)

Supports Investigative Psychology, interpersonal coherence, and geographical profiling.

Bottom-Up Evaluation: Rachel Nickell

Extensive investigative psychology was conducted but the profile was inaccurate. The initial suspect Colin Stagg showed that profile fitted but was not the offender.

Bottom-Up Evaluation: Copson (1995)

75% of 48 UK police forces said that the profiles were useful, only 3% said that it helped identify the actual offender.

Bottom-Up Evaluation: Canter and Larkin (1993)

45 sexual assaults showed support for the circle theory. 91% were identified as marauders.

Bottom-Up Evaluation: Canter and Heritage (1990)

66 sexual assault cases were analysed using SSA and identified clear patterns of behaviour. Supporting the theory of behaviour consistency.

Define: Atavistic Form

Criminals are a sub-species of genetic throwbacks with distinctive facial and cranial characteristics. Proposed by Lombroso.

Define: Eugenics

Controlled selective breeding in humans in the belief that it would improve the human race. (Nazis)

Define: Scientific Racism

The criticism that a theory is prejudice to a community because a race posses characteristics making them superior.

Define: Genetics

The study of heredity and the variation of inherited characteristics based on DNA information.

Define: Adoption Studies

Studies that compare an adopted person’s behaviour to both their biological and adopted parents.

Define: Family Studies

Research conducted among siblings, parents and children to assess evidence for genetic links.

Define: Concordance Rate

The percentage of cases in which both members of a pair have a particular attribute.

Define: MZ and DZ twins

Monozygotic - from one egg (identical)

Dizygotic - from two eggs (fraternal)

Define: MAOA gene

Monoamine Oxidase A provides information for making the enzyme MAOA responsible for breaking down neurotransmitters.

Define: Diathesis Stress Model

Suggests that psychological disorders arise from the interaction of an underlying predisposition and an external stressor.

Define: Neural Explanations

The focus on neurophysiology and neurochemical reasons of offending behaviour.

Define: Neurophysiology

The physical composition of the brain and its functions.

Define: Prefrontal Cortex

The anterior section of the frontal lobe which controls attention, inhibition, emotion and future planning.

Define: Amygdala

Inside the cerebral involved with the experiences of emotions such as aggression.

Define: Antisocial Personality Disorder

Characterised by persistent disregard for social customs and laws, and irresponsible and reckless behaviour.

Define: Mirror Neurons

Special neurons that fire both in response to personal action and the action of others.

Define: Neurochemisty

The study of the chemicals and their reactions in the nervous system.

Define: Neurotransmitters

A chemical substance that is released from neurons that send messages around the body.

Define: Dopamine

A neurotransmitter responsible for pleasure, satisfaction and motivation.

Define: Serotonin

A neurotransmitter responsible for emotional stability, happiness, calmness and focus.

Define: Biological Determinism

The view that behaviour is shaped only by internal biological factors.

Atavistic Form Evaluation: Lombroso

Examined the features and measurements of nearly 4000 criminals and 400 dead criminals. Concluded of an atavistic form.

Atavistic Form Evaluation: Lombroso Scientific Basis

Poorly controlled

Did not compare to a control group

Atavistic Form Evaluation: Kurtzberg et al (1968)

Offered surgery to prisoners with facial defects who thought that their defects made people perceive them as aggressive. Re-offending rates of 42% for those who had facial surgery compared to 70%.

Atavistic Form Evaluation: DeLisi (2012)

Illustrated that the features identified are most likely found amongst those of African descent. Suggesting that Lombroso’s theory was scientifically racist.

Atavistic Form Evaluation: Goring (1913)

After examining 3000 offenders and 3000 non-offenders, there was no evidence that offenders are a distinct group with unusual facial and cranial characteristics.

Genetics: Christiansen (1977)

Over 3500 twin pairs in Denmark, found indication of genetic inheritance.

MZ males: 35% concordance rate

MZ females: 21%

DZ males: 13%

DZ females: 8%

Genetics: Crowe (1972)

50% of the adopted children with criminal bio mothers also had a criminal record by 18. Compared to only 5% in the control adopted group. Suggests biological predisposition.

Genetics: Brunner et al (1993)

It was found that the males of a large Netherlands family had a genetic condition resulting in lower intelligence levels and a deficiency in the MAOA gene which regulates serotonin in the brain and has been linked to aggressive behaviour.

Genetics: Caspi et al (2002)

Followed 1000 males from 3 to 26 Found that

1. maltreatment was a significant predictor of aggression.

2. Low activity of MAOA had no significant effect on aggression

3. 85% of males with low activity MAOA and maltreatment became aggressive in their later life.

Genetics Evaluation: Scientific Basis

Cannot generalise to all non-twins.

Biological Explanations Evaluation: Issues and Debates

Biological Determinism suggests that offending behaviour is determined by genetic factors, therefore the person cannot be blamed.

Does not hold up in justice system. Stephen Mobley (1981) argued he was born to kill because of a family predisposition, this was rejected.

Neural Explanations: Raine et al (1997)

41 murderers were placed under a PET scanner and found that there was reduced activity in the group of offenders in areas such as PFC and the corpus callosum.

Neural Explanations: Buitelaar (2003)

Gave dopamine antagonists to juvenile delinquents which reduced the rewarding feeling causing a decrease in desire to repeat the aggressive behaviour.

Neural Evaluation: Farrington et al (2006)

A group of males who scored highly on APD found that there was some neural differences caused by various risk factors in childhood.

Neural Evaluation: Scerbo and Raine (1993)

Meta-analysis on 29 pieces of research into anti-social adults and children, finding in all cases low levels of serotonin.

Neural Evaluation: Potegal et al (1996)

Found that the stimulation of the amygdala in hamsters led to pronounced aggressive behaviour.

Neural Evaluation: Couppis (2008)

Individuals who engage in certain criminal behaviours may experience an increase in dopamine and as a result seek out those experiences again due to the rewarding feeling.

Neural Evaluation: Keysers (2011)

Offenders only had their empathy reaction activated (mirror neurons) when asked to empathise with the pain of a person in a film. This indicates they are not completely without empathy, but may have a neural switch.

Neural Evaluation: Scientific Basis

Only correlational.

Link between neural differences and APD may be complex and intervening variables may contribute to APD and offending.

May be over simplistic and does not explain all types of crime.

Biological Determinism: Stephen Mobley (1981)

Argued in court that he was “born to kill” because of a biological predisposition but this was rejected. Limits biological explanations