Forensics Flashcards
Define crime
Crime could be defined as an act that goes against the laws of the country in which it was comitted.
Problems defining crime
defining crime is not straightforward
what is considered a crime changes
Culture
defniiton of crime changes cross-culturally
e. g. polygamy/having several wives is seen as a crime in the UK but is allowed in some countries
e. g. adultery is a serious crime in some US states but is not a crime in the UK
Time
definiton of crime changes over time
e.g. homosexuality was a crime until 1967
Age
the definition of crime is not applicable to everyone
the age of criminal responsibility changes from country to country
e.g. in the UK it used to be age 8 but now it is age 10
Circumstance
the definition of a crime changes from situation to situation
e.g. in the UK for an act to be considered criminal 2 core elements need to be seen:
- ACTUS REUS - the act was voluntary, the person was conscious of their behaviour and had control
- MENS REA - intention to commit the crime, ‘guilty mind’
Different ways of measuring crime
how crimes measured
official statistics
Official statistics are gathered by:
The Office for National Statistics or ONS
Meaures crime rates in England and Wales
some types of crime might be difficult to measure
Police records of crime are used
Statistics could be misrepresentative as not all crimes are reported
i.e. fear of reporting or social pressure
offender surveys
The Offending Crime and Justice Survey or OCJS
was conducted in England and Wales
using self-report techniques such as questionnaires to
- ask offenders about drug and alcohol abuse
- gain insight into patterns of offending behaviour
- pick up on unreported crime
The 14th Prisoner Survey
Findings:
- 45% of males drunk when crime committed
- 50% of females reported being drunk when the crime was comitted
victim surveys
carried out by: The Crime Survey for England and Wales or CSEW
a face-to-face survey asking victims (young and old) about their experiences, to try to find trends in crime in the general population
what is offender profiling
The process of identifying a criminal
Top-down approach
also typological profiling
emerged in America, in the 1970s with the FBI (Federal Beareu of Investigation)
uses the experience and intuition of the profiler to develop a profile of a criminal
often used in violent crime such as murders
7 stages
- classifying the type of murder
- deciding if the crime is a delibearte, premeditated one or not
- classifying the victim as high risk or low risk due to their vulnerbality; e.g. low risk targets = children, old people, prostitutes; gives clues to motive
- identifying the level of risk the offender took in committing the crime
- escalaltion - the extent to which the crime has escalated from previous or the potential to escalate
- time factors - time of day of crime; clues to criminal’s daily routine
- location factors - where the crime took place’ clues to criminal’s environment
the 7 stages allow criminal to be classified into 2 personality types: organised or disorganised - typological
organised offenders
- intelligent
- socially competent
- planned atatcks
disorganised offenders
- low intelligence
- loners
- does not plan crimes
Bottom-up approach
English
uses information: research and statisitics on similar type of crimes to develop a profile of a criminal
5 assumptions
- interpersonal coherence - criminal’s behaviour is consistent across situations, e.g. if they are aggressive in everyday life they will commit an aggressive crime
- time and place - where and when did the crime take place
- criminal characteristics - categorising criminals
- criminal career - clues as to extent of offending
- forensic awareness - offenders who have knowledge of forensic investigation may have been through court before
Evaluation of the bottom-up approach
- more objective - based on statistical techniques
Geographical profiling
Stresses the time and location of a crime
4 things to look at:
- location reveals a lot about the offender: location of attack, location of the body etc.
- location is not random - has been chosen for a reason
-
types of offenders: commuters and marauders
- commuters - travel
- marauders - close to home
- comparative case analysis - other crimes seen as being committed by the same person; increases accuracy of profile
The case study of John Duffy as evidence for the successful use of offender profiling to solve a case.
24 sexual assaults and 3 murders
David canter used geographical profiling to build a profile of the crminal, his profile was very similar to Duffy’s actual characteristics
Canter’s profile:
- in mid to late 20s - Duffy was in his late 20s
- knowledgable about railways - Duffy worked for British Rail
- small and physically unattractive - Duffy was 5 foot 4 with acne
- criminal record - Duffy was arrested for raping his wife at knifepoint
Canter found that Duffy had forensic awareness - he burned the bodies of his victims to destroy forensic evidence; something he learned from being arrested
Biological explanations of offending behaviour
criminal behaviour is
Lombroso’s atavistic form
Crminals are born with physical features that distinguish them from non-crminals
e.g. large ears, extra fingers or toes
These atavistic features demonstrate that they are
- more primitive
- uncivilised
- at an earlier evolutionary stage of development
Genes
Twin studies
Christianson (1977) study looked at 3,586 twin pairs where concordance rates in MZ twins (35%) was greater than in DZ twins (13%) suggesting a genetic link
Extra Y chromosome
Jacobs et al. 1965
higher percentage of people with XYY in prison population compared to normal population
They suggested that increased testosterone = increased violence resulting in offending behaviour
Further studies suggest that XYY resulting in impulsivity and low IQ more likely to result in offending behaviour
Brain physiology
…
Biochemistry
3 biochemicals implicated in offending behaviour
noradrenaline
high levels linked to violence and aggression
serotonin
low levels lead to more impulsive behaviours
dopamine
links to addiction and drug abuse which makes crimes more likely
Evaluation of biological explanations of offending behaviour
Lombroso’s atavistic form
no control group used - difficult to make conclusions
deterministic - no free will to choose behaviour, criminals can’t be blamed for their behaviour
those in his sample may have had psychological disorders or learning disabilities that may have played a role in their behaviour or their physical appearance
historical context - time where crime seen from a religious persepctive
Twin studies
concordance rates tend to be low
concordance rates not 100% so environment must play a role
Biochemistry
research into biochemistry is correlational rather than causal but implies that offending behaviour can be treated
reductionist - simplifies criminal behaviour
