Main Areas of Investigative Psychology

• Investigative Psychology (IP): It focuses on establishing an empirical foundation for the ways in which criminal actions are evaluated and comprehended so that the detection of crime is effective and legal proceedings are suitable.

• Three Processes of IP

  • Information Retrieval

  • Decision-making

  • Criminal behavior

Information Retrieval

• Police investigation crime reports to gather, assess, and use them.

• Scientific research on human perception and memory, as well as psychological studies on report reliability, validity, and evaluation, can benefit this activity.

• IP concerns itself with what information is used in investigations and the work that supports them, as well as how that data is obtained.

• Much of this work in property rights falls under the heading of real-world research and comprises building and executing content analysis methodologies relevant to these kinds of data sources.

• IP information retrieval requires reevaluating the most accurate recording measurement units for crime scene investigation.

• Pre-IP information gathering methodologies used to build research data sets lacked explicit descriptions of crime scene-related acts.

  • This lack of conceptual accuracy raised concerns about the authenticity of studies based on data collected by these pre-IP tools.

• Early crime scene classification models used psychological processes to classify criminals by motivation.

  • Early IP research developed objective measurement methods to solve this methodological challenge.

  • Instead of subjective crime scene evidence, they show the perpetrator's physical actions.

  • Building more relevant measurement tools can teach data collectors.

Measurement Tools

• Homicide Profiling Index – Revised to include Rape and Sexual Offenses: A measuring device intended for use in collecting data from police case files in accordance with established best practises.

• This is a comprehensive instrument based on crime scene components that can be collected from a case file.

• It consists of 312 variables and 27 subgroups of variables that can be classified into 6 broad categories.

  • case file contents

  • precrime behaviors

  • crime scene behaviors

  • postcrime behaviors

  • victimology

  • offender background

Decision-Making

• Police investigate crimes by gathering, analysing, and using multiple accounts.

• Investigators find decision-making hardest.

• The investigation procedure's chronology can inform decision-making.

• An enquiry gathers and processes a lot of information, making it hard to retain and recognise the most significant parts.

• Context-free decision making is impossible because the investigator's past experiences influence all decisions.

• People cannot avoid biases in perception and decision-making.

• Social psychology literature shows that people selectively perceive what they want to see and use this information to create and confirm their decisions.

• Cognitive biases and bad decisions can occur.

• Heuristic bias can impair investigative decision-making, hence strategies to limit it have been developed.

• Intellectual property decision-making research focuses on practitioners to demonstrate how crime scene information affects decision-making.

• Investigators must use their knowledge about the offender(s) to identify and choose suspects or lines of enquiry.

• They must find the most likely culprit features and experimentally confirm their findings.

Criminal Behavior

• IP's third focus is building police investigations' inferences.

  • This entails understanding and modelling criminal behaviour.

  • Criminal behaviour analysis is based on the assumption that offenders' traits and crime scene behaviour are linked.

  • The A🡢C equation links offender characteristics to offending actions.

• Behavioral crime scene investigation and offender profiling research has focused on individual differentiation, behavioural consistency, and criminal characteristic inferences.

  • Individual differentiation: The purpose of this study is to identify subgroups of crime scene types and differentiate between the behavioural actions of criminals.

  • Behavioral consistency: This seeks to comprehend both the progression of a criminal's career and the individual's consistency across a series of crimes, i.e., whether the same actions are displayed at each crime scene across a series of offenses.

  • Inferences about offender characteristics: Its aim to determine the nature of the coherence between the most likely features of an offender based on the way an offender behaves at the time of the crime and is at the core of criminal profiling.

Individual Differentiation and Classification

• Canter (1995, 2000) in the original sketching of the A🡢C equation, makes the key point that for offender profiling to operate, it needs to assess the salience of the variables that are employed for the crime scene classification process.

  • IP began with a focus on salience and identifying the crime scene actions that best distinguish behavioural subtypes.

• A sexual crime's sexual element or a homicide's victim's death would be present in most crime scenes.

  • Certain crime scenes exhibit highly individualised behaviours that are not suitable for a model that attempts to summarise crime scene characteristics.

  • To identify one crime from another, the most significant crime scene characteristics must be identified to classify crime scenes into subtypes with similar traits.

  • Each crime scene subtype has its own characteristics, yet their activities will have a psychological connection.

  • This gives a framework for comparing and classifying crime scenes based on evidence.

• The first IP homicide model, which followed IP principles of information retrieval and analysis of criminal behaviour from case files, connected activities within each subtype and differentiated crime scene subtypes (see Salfati & Canter, 1999). This model identified these subtypes:

  • Expressive-Impulsive

    • This type of homicide involves a series of erratic and impulsive actions against a victim with personal importance in an emotionally charged situation.

    • These homicides are often impulsive because the culprit utilises a weapon found at the spot or brings one, emphasising a violent encounter.

    • These killers often have a history of impulsive and violent crimes, which shows how they have behaved with others in the past and how they handle conflict in general.

  • Instrumental-Opportunistic

    • This type of homicide targets vulnerable victims of opportunity used as conduits. Strangulation, kicking, and punching injure the victim.

    • In certain cases, the perpetrator steals goods and/or sexually assaults the victim.

    • These offenders tend to commit robbery and burglary rather than theft.

  • Instrumental-Cognitive

    • This category of homicide has a cognitive emphasis, victims are objectified, the offender keeps calm throughout and after the crime, and they strive to remove forensic evidence, transport the body, or dispose of the body.

    • These behaviours show that the perpetrators are purposefully distancing themselves from the victim and crime, therefore removing themselves as suspects. These crooks know forensic evidence.

    • These cognitive crimes are committed by experienced criminals who have served time in prison.

• Developing crime scene subtype categorization and differentiation models requires identifying the strongest psychological themes.

  • Psychological patterns or themes of crime scene behaviour are more important than individual behaviours.

• Intelligence Penetration (IP): This is a branch of study that seeks to categorise criminal conduct into separate subtypes whose behaviours share common psychological elements.

  • This technique to classification and individual distinction is fundamental to behavioural analysis in IP and serves as the foundation for all research in the discipline.

• Early studies produced categorization methods and instructed law enforcement officials to use them, but did not provide a criterion to classify a criminal based on their behaviour.

  • Hybrid instances were found in many crime sites in the first decade of forensic research.

  • IP work has focused on refining classification model behaviours to better identify one type from another, making classification models more robust, and reducing the number of hybrid cases or redefining hybrids as a separate type.

Behavioural Consistency and Linking

• The second area of focus in the analysis of criminal behaviour is behavioural consistency.

  • This field of study has expanded the (A)ctions portion of the A-C equation to A-A-A and aims to examine how offenders' actions may be consistent over time.

  • Both the relevance of the behaviours and the individuality of crime scene subtypes are crucial to the selection of the analytic units for any study attempting to quantify consistency patterns.

  • Early IP study on this topic revealed that hybrid crime scenes are associated with a lower level of series consistency.

  • Salfati and Bateman (2005) released the first study in the field seeking to provide a baseline understanding of how consistent offenders are throughout their series, stating that 70% of series had hybrids.

• IP created the Model for the Analysis of Homicide Trajectories and Consistency (MATCH).

  • This method evaluates series consistency, not exact matches between crime sites.

  • It also discusses how hybrid crime scenes might define some TV programmes.

  • In a serial homicide research, the MATCH approach classified the majority of series according to a dominating trajectory pattern, while consistency analysis only classified half as many series.

• The MATCH system for conceptualising behavioural patterns includes six distinct trajectories that offenders engage in during their series of offences.

  • Consistent Pure Type: Each crime scene displays the same dominant classification subtype at each crime scene.

  • Pure Type Switcher: An offender switches between two crime scene classification subtypes throughout their series.

  • Consistent Hybrid: Each crime scene is a hybrid subtype, and where each crime scene in the series displays this same hybrid subtype.

  • Pure Type–Hybrid Switcher: Each crime scene displays either a pure subtype, or a hybrid subtype that includes the pure subtype.

  • Double Pure Type–Hybrid Switcher: Crime scenes within a series switches between two types throughout the series, or a hybrid of these two pure types.

  • Inconsistent Type: Aims to describe what the testing of the model found to be the rare series that do not display a trajectory in line with the above outlined patterns

Inferences about Offender Characteristics

• Offender profiling: It is the practise of inferring the characteristics of a criminal based on his or her behaviour at a crime scene in order to prioritise suspects.

  • It is vital to remember that the objective is not to identify a specific perpetrator, but rather to establish the most likely offender traits connected with the sorts of activities found at the crime scene.

• The focus of this study has been on five main categories of characteristics:

  • demographical information

  • criminal history

  • geographical profiling – the location of the offender’s most likely home area

  • offender motivations

  • offender narratives

  • offender psychological and clinical characteristics

• IP emphasises empirically derived models of behaviour and work for investigative practises.

  • This study focuses on offender factors including age, education, relationship to victim, and criminal history.

• Psychology, personality, and clinical assessments have been studied.

• Motivation and offender narratives were also examined.

  • This study examined offenders' self-perceptions and relationships with others to determine who they target, why, and how.

Investigative Psychology in Practice

• This figure shows the iterative process, which begins with determining the most important law enforcement and investigative questions.

• We then develop important research hypotheses to lead the research and enable a full analysis to answer these practice-based concerns.

• We use the answers in training to make the study practical.

• It is crucial to analyse how this new evidence-based information affects investigative practise and whether knowledge gaps remain.

• This must be done while evaluating the training process for the best ways to translate scientific information into investigative practise.

• After practise, new questions are created to refine and broaden the original ones.