What is IP

What is Investigative Psychology?

Brief Definition:
Investigative Psychology is the scientific discipline concerned with the psychological principles, theories and empirical findings that may be applied to investigations and the legal process.

Detailed Definition:
Investigative Psychology is a framework for the integration of a diverse range of aspects of psychology into all areas of criminal and civil investigation. It is concerned with all the forms of criminality that may be examined by the police, from arson and burglary to murder, rape or even terrorism. The discipline also extends to cover those areas of activity that require investigation but may not always be conventionally within the domain of police services. These may include matters such as insurance fraud, corruption, malicious fire setting, tax evasion or smuggling. Increasingly, issues of crowd control and public order are also being studied by investigative psychologists. The focus is on the ways in which criminal activities may be examined and understood in order for the detection of crime to be effective and for legal proceedings to be appropriate. As such, Investigative Psychology is concerned with psychological input to the full range of issues that relate to the management, investigation and prosecution of crime.

This includes:

  • Examination of the styles and patterns of criminal action and how these relate to offenders' psychological and social characteristics (e.g. Investigative Inferences & Offender Profiling, Geographical Profiling, Modelling Offence Styles, Psychological Correlates of Offence Style)
  • Analysis of the investigation and legal process itself including the activities and decisions of detectives, crime analysts and lawyers (e.g. Investigative Strategy, Interviewing and Questioning, Prediction of Violence, Detective Decision-Making)
  • Assessment of the validity of investigative material and legal testimony (e.g. False allegations ,False Confessions, Eyewitness Testimony, Detecting Deception)


Schematic Overview of Investigative Psychology

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Moving Beyond Offender Profiling to Investigative Psychology
The contributions that psychologists can make to police investigations are most widely known and understood in terms of "offender profiles". Offender profiling, as typically practised, is the process by which individuals, drawing on their clinical or other professional experience, make judgments about the personality traits or psychodynamics of the perpetrators of crimes. From the perspective of scientific psychology, such a process is flawed in its reliance on clinical judgment rather than actuarial assessment. These flaws have been shown in extensive studies first reviewed by Meehl in 1954. The clinically-derived theories upon which much "offender profiling" has relied are equally questioned by research psychologists.

The lack of scientific rigor evident in the profiling process has for two decades driven proponents of Investigative Psychology research to map out the scientific discipline (origins) that could underpin and systematize contributions to investigations. Interestingly, this more academically grounded approach is opening up the potential applications of psychology beyond those areas in which "profiling" first saw the light of day, rather than moving away from operational concerns. Early profilers insisted that their skills were only relevant to bizarre crimes in which some from of psychopathology was evident, notably serial killing and serial rape, but investigative psychologists now study and contribute to investigations across the full spectrum of illegal activities.

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Operational Applications
There are a wide range of practical applications of Investigative Psychology. Professor David Canter has proposed that these may be categorized under ten classes of operational question that police and other investigators as well as the courts face in the course of their activities.

  1. Salience. What aspects of a crime are the salient ones?

    So much of apparent significance can happen in a crime that it is not necessarily obvious to the investigator what are the features of the crime on which attention should be focused. These features may help investigators to understand the crime and its context more fully and may fruitfully point to the type of individual who may have committed the offence.
  2. Suspect Elicitation. What searches of police records or other sources of information should be carried out to help identify the offender?

    This is a question about what the dominant features of offenders are likely to be. This can open up searches of particular areas or databases, inviting information from the public, or working with informants. All these processes can draw upon a fuller understanding of the crime and the sorts of people who commit such crimes.
  3. Suspect Prioritization. Which of the possible suspects are most likely to have committed the crime?

    The personal characteristics and previous behavioural patterns of the offender, as inferred from study of the crime, can help the police to distinguish the perpetrator of a given crime from other known offenders the police may be considering. In operational terms, this becomes a question, for example, of which suspects should be drawn from police or other databases for the most detailed scrutiny. So, for example, indications that the Investigative Psychologist could give about the likely criminal history of an offender who has committed a certain type of crime in a certain way, may be helpful to police searching through their lists of possible suspects.
  4. Offender Location. Where is the offender most likely to have a base?

    Ideas about where an offender is likely to be living can shape an investigation and the deployment of police personnel and resources. Understanding the geographical patterning of an offender's criminal activities and how this relates to his or her home base has huge potential significance in operational terms.
  5. Linking Crimes. Which crimes are likely to have been committed by the same perpetrator(s)?

    The linking of crimes to a common offender/s has many advantages for police investigations. Such linking requires the determination of what it is about any given offender that is sufficiently internally consistent, from one crime to the next, to suggest that a single person is responsible for the crimes. If most burglars use forced entry it is unlikely that will be able to link together two burglaries committed by the same person who also happens to use forced entry. Of course, if a burglar has a mode of operating that is as unique to him as a signature, then that can be used to link his crimes, but it is rare for any criminal to reveal such "signatures" consistently. It therefore follows that issues of salience in the offender's actions are taken to a further level when linking is considered. The salience of the action in distinguishing one offender from another needs to be studied as well as its salience in distinguishing one offence from another.
  6. Prediction. Where and when will the offender commit his/her next offence and what form might that take?

    When the police are investigating a series of crimes, predicting where and when the next offence will occur becomes a key operational concern. The likely severity of the offence, for example, whether violence is likely to escalate, or whether a different form of offence is probable, is also of operational significance.
  7. Investigative Decision Making. In what ways can the investigative process be improved?

    The actual details of how investigations are organized and the processes of decision making are open to psychological scrutiny and can be influenced by knowledge of the cognitive and social processes involved. This leads on to the consideration of the most effective decision support tools and the development of such tools.
  8. Information Retrieval. How can the collection of information in an investigation be made more effective?

    The interviewing of suspects, witnesses and victims, as well as the harnessing of information from other public and private sources can all benefit from an understanding of the cognitive and social processes involved in these activities as well as the data management skills that are part of a psychologist's training.
  9. Evaluation of Information. How can the information that becomes available be assessed?

    The most obvious area of psychological study here is in the detection of deception. However, other aspects of the validity and reliability of information obtained is open to systematic scrutiny and improvement, particularly by drawing on psychometric tools.
  10. Preparing a Case. What sense can be made of the offence that will help to organize the legal case?

    In court, the prosecution - and the defense - draw implicitly on lay models and ideas about human behaviour to make their case. Formal psychological theories can be used to structure legal cases, and this will on occasion improve the quality of arguments.

Psychology can contribute to these operational matters on two levels. Most significantly, Investigative Psychologists are able to provide substantive knowledge, based on empirical studies, and these studies can, increasingly, provide direct answers. Secondly, psychology can provide a framework for understanding the processes that police must go through in attempting to find the answers. Conceptualizing these processes in familiar terms allows psychologists to suggest improvements.

Empirical Solutions to the "profiling equations"
At the heart of these ten operational questions are what have become known as the "profiling equations" (after Canter, 1995). These are equations that provide the scientific bases for inferring associations between the actions that occur during the offence - including when and where they happen and to whom - and the characteristics of the offender, including the offender's criminal history, background, base location, and relationships to others. They are also referred to as the "A => C equations", where
A are the actions related to the crime and
C are the characteristics of typical offenders for such crimes and
=> is the argument and evidence for inferring one from the other.

Investigative psychologists have conducted, and continue to conduct - a wide range of empirical studies of different types of crime, with the purpose of establishing solutions to these equations, in the hope of providing objective bases for investigative inferences.

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