The Investigative Psychology Research Unit (IPRU)

About the lab

The Investigative Psychology Research Unit (IPRU) heads numerous research projects in collaboration with international police forces and federal agencies relating to the analysis of crime, specifically with a focus on offender profiling, crime scene analysis and linking serious serial crime. The unit also provides training of students, researchers and professionals in investigative psychology and crime scene analysis.

For more information on the IPRU please see:

Featured projects (7)

The HIP project focuses on homicides involving prostitutes and sex workers. This project aims to improve our understanding of the distinct behavioral patterns and types of offenders who exclusively target this high risk victim group, as well as our understanding of how victimization of prostitutes fits within a generalized pattern of non-target specific violence. Issues of solvability and behavioral linkage are also being examined. The dataset used in this study consist of a total of 83 series, with 519 victims from six different countries. Of these, 44 are Sex-Worker series where all victims are sex workers, and 39 are Mixed-Victim series which include both sex workers and non sex workers. Information for cases was collected and coded using the Homicide Involving Prostitutes (HIP©, Salfati & Sorochinski, 2016) coding dictionary specifically developed for the purpose of this project. The dictionary contains 66 variables pertaining to victim and offender demographics, crime type and crime scene characteristics, as well as the outcome of the case.
The SOP project is an interdisciplinary project looking at the relationship between behavioral crime analysis (i.e. offender profiling) and risk assessment of sex offenders. This project aims to combine the knowledge base from both of these fields in order to refine their core principles and improve upon both processes. Issues of behavioral consistency, salience, and outcome prediction are also addressed.
In order to fully understand the issues practitioners face when applying what they have learnt into practice, a more practical understanding must be had of the exact issues practitioners face during and post-training when aiming to ‘translate’ what they have learnt to their day to day practice. Feedback from practitioners on the issues that occur when aiming to implement training is key as part of a full understanding of the process of evidence-led-practice, and its implementation. Related to this may be a number of influencing and contributing factors. Ultimately, all of these factors will inter-relate on the success of the outcome of the training, as evidenced by the ability of the practitioner to implement the training objectives into practice. Work in the IPRU currently focuses on best practice in training and implementation of research into practice, as a basis for Evidence Based Practice.
The Homicide Profiling Index – Revised to include Rape and Sexual Offenses (HPI-R©) (Salfati, 2010) is a coding dictionary designed to be used as a tool for collecting data via police case files. It was first created in 1994 and has since then been refined, with several key changes made in order to stay up to date regarding the direction that homicide crime scene research has been heading in. The most notable change in the HPI-R is the addition of variables pertaining to live victims, including rape/sexual assault offenses. This is a direct response to the argument that an offender’s series often includes multiple types of crimes, and each crime is of importance when conducting research and analyzing influences on offender behavioral consistency over a series (Salfati, 2008). The HPI-R contains over 300 variables and involves the scoring of pre-crime, crime, post-crime, offender background and victimology behaviors and characteristics. The overall reliability of the use of the HPI-R post-training has been shown to be over 89%. Training and Certification from the IPRU is available to students, researchers, analysts, investigators and other practitioners.
The main aim of behavioral crime scene analysis, otherwise known as offender profiling, is to analyze the way an offender commits their crime, to establish discernable patterns and behavioral sub-types, and then link sub-types of crime scene actions to the most likely offender background characteristics, and use this in criminal investigations as a primary tool for the police to narrow their suspect pool down to statistically the most likely type of offender. Individual differentiation is a key component of offender profiling research and aims to establish differences between the behavioral actions of offenders and identify subgroups of crime scene types. Research in the IPRU has focussed on identifying the most salient (important) crime scene features to focus on as well as the most appropriate unit of analysis that can be used to reliably differentiate crime scenes by different offenders. Our studies focus on empirically testing various crime scene classification schemes and understanding the factors that may influence offender’s behaviors, such as the type of victim and the situational aspects of the crime. Ultimately, offender profiling research is aimed at understanding how behaviors exhibited during a crime can help infer characteristics of an offender. This is often expressed as the A->C equation, i.e. Actions-to-Characteristics.

Featured research (1)

Sex workers as a group are one of the more common targets in serial homicide, yet the most likely to go unsolved. Part of the reason for this is the difficulty in linking individual crime scenes to a series, especially in those series where offenders not only target sex worker victims but also target non-sex worker victims. Inconsistencies in both victim targeting and behaviors engaged in across series add to the difficulties of linking and solvability in these types of crimes. The current study aimed to add to the current body of literature on serial crime linkage by examining not only the most salient behavioral indicators useful for crime scene classification of serial homicides that involve sex worker victims but also examine the trajectories of behavioral change that can help link apparently inconsistent crime scenes and proposes the new Model for the Analysis of Trajectories and Consistency in Homicide (MATCH). The study examines 83 homicide series, including 44 (53%) series where all victims were sex workers and 39 (47%) series that included a mix of sex workers and non-sex worker victims. Using the MATCH system allowed for the majority of series to be classified to a dominant trajectory pattern, over half as many as a traditional consistency analysis that focusses on behavioral similarity matching. Results further showed that Sex Worker Victim series were almost three times more consistent across their series than Mixed-Victim series, not only in victim selection but also in the overall behavioral patterns. Findings are discussed in line with theoretical and psychological issues relating to understanding the nature of behavioral consistency and the importance of going beyond simple matching toward a model that allows for the identification of consistency in seemingly inconsistent series, as well as investigative implications relating to linking serial crimes.

Lab head

C. Gabrielle Salfati
  • Department of Psychology
About C. Gabrielle Salfati
  • Professor C. Gabrielle Salfati is part of the first group of people who emerged within the new field of Investigative Psychology, and was instrumental in its development as an international research field on the empirical analysis of violent criminal behavior, in particular the advancement of the science of offender profiling. Her main areas of expertise are homicide and sexual offenses, in particular with reference to developing key research methodologies related to offender profiling, classifications of violent crime, and linking serial crime. All of the work in the IPRU is developed in collaboration with law enforcement agencies internationally. She has presented and published widely and internationally on her work, and trains practitioners.

Members (5)

Marina Sorochinski
  • St. John's University
Rosanne Libretti
  • Brandeis University
Sneha Gupta
  • City University of New York - John Jay College of Criminal Justice
Kimberley Schanz
  • CUNY Graduate Center - John Jay College of Criminal Justice
Eric Korzun
  • City University of New York - John Jay College of Criminal Justice