Criminal Profiling Flashcards
What is offender Profiling/ Criminal Profiling?
A process by which “offender characteristics can be deduced from a detailed knowledge of offence characteristics. i.e making an inference from crime and crime scene —-> information about offender?
What type of crime is criminal profiling often used for?
Most often used for serial/serious crime (rape and murder)
What information about the offender might criminal profiling generate? (give a few examples)
Age, Ethnicity, Gender, General appearance, Socioeconomic status, Residence description, Education history, Relationship status, Employment background, Criminal record, Psychiatric history, Personality, Familiarity with geographic area, Social and sexual development, Pre and post offence behaviour
Name the 3 main approaches to profiling
Clinical practitioner/Criminal investigative. Statistical/Scientific. The FBI (typological) Approach.
What are the Three manifestations of offender behaviour at the crime scene? (crime scene analysis)
Modus Operandi, Signature and Staging
In crime scene analysis in regard to the manifestation of offender behaviour at the crime scene - what is Modus Operandi?
Method used to accomplish crime (dynamic and malleable)
In crime scene analysis in regard to the manifestation of offender behaviour at the crime scene - what is Signature?
unique and integral part of offender behaviour: their “calling card” (constant and enduring).
In crime scene analysis in regard to the manifestation of offender behaviour at the crime scene - what is Staging?
efforts to alter crime scene
What are the main features of the FBI approach to criminal profiling? (3 things hint: Reliance on?, what type of crime? what type of relationship with the investigative team?)
- Reliance on experience, intuition, expertise of profiler. 2. Focus on serious, bizarre and extreme crimes. 3. Extensive contact with investigative team.
Who is championed as the pioneer of investigative psychology (in Britain)?
David Canter
What is the Investigative Psychology approach to criminal profiling? (2 things hint: type of evidence, hypotheses)
- Measurement of statistical relationships rather than intuition/experience 2. Hypotheses about what offender characteristics relate to what offence behaviour and evidence for relationship.
What are some central problems to investigative psychology? (4 things)
(low) Salience of behaviours, Distinguishing between offenders, Inferring characteristics, linking offences.
What are the three key assumptions of Investigative Psychology?
- CONSISTENCY: The actions of any given offender are consistent across offences 2. DIFFERENTIATION: There will be psychologically important variations between crimes that relate to differences in the people who commit them 3. INFERENCE: Similar offence styles will be associated with similar offender characteristics
In regards to investigating psychology, what is the assumption of Consistency?
The actions of any given offender are consistent across offences
In regards to investigating psychology, what is the assumption of Differentiation?
: There will be psychologically important variations between crimes that relate to differences in the people who commit them
In regards to investigating psychology, what is the assumption of Inference?
Similar offence styles will be associated with similar offender characteristics
What are some limitations of the FBI approach to criminal profiling? (i.e disorganised vs. organised?)
- Crime scenes (and offenders) have both organised and disorganised characteristics. - dichotomy. 2. Data on associations is drawn from a pool of offenders that are all male and predominately white - thus may not be relevant for female or non-caucasian.offenders.
In regards to analysis in investigative psychology, what is facet theory?
the idea that different facets of the offence (e.g., type of weapon, what was taken from scene) are related to different aspects of the offender (e.g., age, previous criminal record) {Boon and Davies, 1993}
What are the main features of investigative psychology? (4 things)
- Emphasis on need for research base 2. Statistical approach for relationship between crime scene and offender characteristics 3.Rejection of clinical intuition 4.Greater range of crimes
What is the availability heuristic?
The availability heuristic is a mental shortcut that occurs when people make judgments about the probability of events by how easy it is to think of examples. The availability heuristic operates on the notion that, “if you can think of it, it must be important.” The availability of consequences associated with an action is positively related to perceptions of the magnitude of the consequences of that action. In other words, the easier it is to recall the consequences of something, the greater we perceive these consequences to be. Sometimes, this heuristic is beneficial, but the frequencies that events come to mind are usually not accurate reflections of their actual probability in real life.
What is case linkage?
“Identifying behavioural similarities between offences that point to them being committed by the same perpetrator (Woodhams & Grant, 2006)
Other names for case linkage?
Linkage analysis, comparative case analysis, behavioural analysis
What are the uses of case linkage? (4 things)
- Efficient deployment of limited police resources 2. Accumulation of physical evidence from different crime scenes (Grubin, et al., 2001) 3. Each individual victim gains credibility from the others (Davies, 1992). 4.Similar fact evidence in legal proceedings (Woodhams, Hollin, & Bull, 2007).
In regards to case linkage, what is a linked pair and what is an unlinked pair?
Linked pair = known to be committed by same offender Unlinked pair = known to be committed by same offender
Define ‘analytical stratergies” for case linkage, give examples.
Across-crime similarity coefficients used to quantify behavioural stability and distinctiveness e.g. Jaccards coefficients, logistic regression, ROC analysis
What is Jaccards Coefficient (analytical stratergy for case linkage)
The Jaccard index, also known as the Jaccard similarity coefficient is a statistic used for comparing the similarity and diversity of sample sets. s = event- Q non-union to event-D / Event-Q union to event-D = P/p+q+d where p = number of variables that are positive for both q = number of variables that are positive in Q but not D d = number of variables that are positive in D but not Q
What is logistic regression? (analytical stratergy for case linkage)
In statistics, logistic regression or logit regression is a type of regression analysis used for predicting the outcome of a categorical dependent variable based on one or more predictor variables. Logistic regression measures the relationship between a categorical dependent variable and one or more independent variables, which are usually (but not necessarily) continuous, by using probability scores as the predicted values of the dependent variable.
What is ROC analysis? (analytical stratergy for case linkage)
In signal detection theory, a receiver operating characteristic (ROC), or simply ROC curve, is a graphical plot which illustrates the performance of a binary classifier system as its discrimination threshold is varied. It is created by plotting the fraction of true positives out of the positives (TPR = true positive rate) vs. the fraction of false positives out of the negatives (FPR = false positive rate), at various threshold settings. TPR is also known as sensitivity (also called recall in some fields), and FPR is one minus the specificity or true negative rate.
Limitations to analytical stratergies of case linkage? (3 things)
- What similarity coefficient to choose (linking performance varies depending) 2.How choice of behaviours influences degree of similarity and distinctiveness found 3. How to identify an appropriate decision threshold
There is (some) evidence that case linkage is effective in ___what___ types of crime, and why is it useful for them?
Murder, commercial robbery, adult & juvenile sexual offences, residential and commercial Burglary Because they contain more behavioural consistency and distinctiveness - particularly for control behaviours and spatial behaviour (inter-crime distance)
What factors affect the consistency of an offender’s Modus Operandi (mode of operation)?
Experience, maturation, education, victim reaction, interruption etc
What are the characteristics of behaviours that are better to use than others when behaviourally linking crimes?
- Behaviours that are NOT common to all offenders - behaviours that are uncommon or unique
- Behaviours that have been shown to have greater consistency than others due to how situation-dependent they are
What is the “homology assumption” in criminal profiling/crime linkage?
The assumption that the characteristics of offenders are homologous with their crime scene. i.e that they have the same relation/structure
What is a limitation of research regarding the assumption of offender consistency and distinctiveness?
Studies sample convicted offenders (i.e not those who remain un-caught)
What does the age-crime curve suggest about the onset of criminal offending?
Offending increases from around age 8, peaks at age 16-17 and falls away sharpely from 18+
What two factors regarding the reporting of crime contribute to the ‘dark-figure’ of unreported crime?
- Not knowing that a crime has occured (since one must have a belief that a crime has occured to report it)
- Willingness to report crime (some situations/people reluctant to report crime)
What are some factors affecting the quality (meaningfullness) of official criminal statistic?
- lack of uniformity across police forces (not including figures from other agencies, data recorded in a way that is incompatible)
- Recording of multiple crimes as one incident
- Changes over time e.g in law (criminal damage, homosexuality, marital rape)
- Aggregation of dat into broad crimes types, therefore, miss more specific data
What factors influence the perception that a crime has increased even if it may not have?
(crime detection & targetting)
- Police priorities - resources into catching certain types of criminals/crimes—> catch more of that type of offender = appearance that there are more of those types of offenders
- Increased public awareness (people noticing crime, attentionally biased to crime, confirmation bias) e.g drugs, rape and drink driving
- Reduction in stigma (sexual assault) - more people willing to report and talk about
Does the ‘dark-figure’ in criminsal satistics apply to crime surveys (method)? if so, why?
Yes. Still requires belief that crime has occured and willingness to report crime. Survey may be answered untruthfully if the offender is present of if the person is trying to protect an offender
List factors contributing to incomplete data in crime surveys (surveys regarding victimisation)
- No self-report for some crime (murder) and some victims (children, homeless, tourists)
- ‘Victimless crime’ (drug posession, fraud)
- Memory for vicitimisation (forgotten victimisation)
- Recency of events - more recent events favoured in reporting
- Seriousness - whether the criminal event is seen as serious or not
- Repeat victimisation - person may be ‘used to it’ and not report, multiple crimes reported as one instance
- Reactivity of participants - participation in crime research increases awareness about crime and leads to behavioural changes that reduce (or possibly increase) their risk of being a victim.
how might the reactivity of participants affect the completeness of criminal survey data (victimisation survey)
participation in crime research could increase awareness about crime and lead to behavioural changes that reduce (or possibly increase) the risk of being a victim.
What are the two groups of offenders in Moffitt’s typology?
- Life course persistent
- Adolescence Limited
In Moffitt’s Typology, what are ‘life course persistant’ offenders?
Early onset, rare, long criminal
careers, smaller group, accounts for
large amount of offending.
In Moffitt’s Typology, what are ‘adolescence limited’ offenders?
Middle onset (adolescence), common,
short criminal careers, larger group,
accounts for a small amount of
offending over time
What factors influence the duraion of offending and how?
Age of onset = longer criminal career
Multiple offenders = greater mean number of years offending
What are risk factors?
- A characteristics of the individual or his/her environment (e.g., family, neighbourhood) that are related to the increased probability of a negative outcome.
- Evidence of the risk factor must precede evidence of the development of the outcome.
- Risk factors are not necessarily causally related.
