Geographical Profiling Study Notes

Lecture Overview

  • Introduction to Crime Analysis and the Mapping of Crime

  • Geographical Profiling (GP)

  • Process & Method of GP

  • Principles and Theories of GP

  • Examples of the practical use of GP

  • Computerised Geographical Profiling, including Geographic Information Systems (GIS)

Early Research in Geographical Profiling

  • Chicago School History

    • Group of urban sociologists led by Robert Park

    • Studied importance of geography in understanding crime

  • Mapping of Crime and Social Characteristics in Chicago

    • Shaw and Myers (1929) mapped 9000 home addresses of juvenile delinquents

    • Findings: homes clustered in areas of ‘physical deterioration, poverty, and social disorganization’

    • Mapped by hand, highlighting inefficiency compared to technology

  • Technological Advancement

    • Development of computers in the late 1960s/70s allowed for automatic crime mapping

    • Introduction of Geographic Information Systems (GIS) for data management

Crime Mapping and Analysis

  • Basic Tools and Methods

    • Use of maps and pins to visualize crime data

    • Lost crime patterns (i.e., historical data not captured)

    • Static representation of crime, making it difficult to read

    • Short-term utility rather than long-term analytical value

  • Importance of Technology

    • Enables visualization of patterns across entire jurisdictions

    • Identification of crime hotspots using computer mapping tools

Geographical Profiling (GP) Defined

  • Definition

    • GP is an information management strategy for serial violent crime investigations.

    • Employs mathematical models and psychological principles to analyze offender movements.

    • Aims to understand significance of chosen locations and the meaning of the offender's journey.

    • Does not directly solve cases but aids in managing investigative information.

Key Contributors to Geographical Profiling

  • Kim Rossmo

    • Affiliated with Simon Fraser University

    • Developed a crime model that predicts crime likelihood based on offender’s residence, workplace, and leisure activities.

  • Activity Space Concept

    • Everyone has an ‘activity space’, influencing crime patterns based on daily movements.

    • Questions how crime location relates to potential offender residence.

Conditions for Geographical Profiling Feasibility

  • Five Conditions Necessary for Effective GP

    • Minimum of five linked crimes (though analyses can occur with fewer)

    • Crimes must be linked to the same offender, and the series should be relatively complete.

    • Offender must not commute into the area of criminal activity.

    • The offender must not change anchor points during the series.

    • The distribution of suitable targets should be relatively uniform around the offender’s home region.

Practical Applications of GP

  • Uses of Geographical Profiling

    • Developing geographic profiles to estimate offender residence based on crime locations.

    • Examining differences/similarities between traveling versus stable offenders.

    • Identifying catchment areas for potential suspects.

    • Performing time, speed, and distance calculations to assess offender travel to crime sites.

    • Mapping crime distributions to identify hotspots.

Investigative Questions to Consider

  • Key Locations and Time

    • Site selection based on offender habits and crime patterns.

  • Target/Structural Backcloth Analysis

  • Hunting Style Categories

    • Hunter: actively seeking victims.

    • Poacher: opportunistic, taking advantage of unguarded situations.

    • Troller: seeking easy, fleeting opportunities.

    • Trapper: creating situations to ensnare victims.

GP Process Steps

  1. Crime Commission: A series of crimes occurs.

  2. Investigation: Traditional investigation methods are employed.

  3. Link Analysis: Analyze connections among crimes.

  4. Psychological Profiling: Develop psychological profiles of unknown subjects.

  5. Geographical Profile Construction: Create profiles based on gathered evidence.

  6. New Strategies: Adopt new investigative strategies based on profile findings.

GP Methodology

  1. Examination of Case Files: Reviewing all available case details.

  2. Crime Scene Inspection: Analyzing the crime scene for clues.

  3. Collaboration with Investigators: Meetings and discussions with leading investigators.

  4. Crime Statistics Analysis: Assessing local crime and demographic data.

  5. Mapping Studies: Reviewing street, zoning, and transit maps.

  6. Data Input and Reporting: Enter all information into computer systems for overall analysis and submission of reports.

Finding the Offender

  • Information Collection: Gathering information through various means

    • Direct and indirect evidence collection.

    • Public tips, witnesses, informants, friends, family, and neighbors.

    • Utilizing databases, criminal records, police files, DMVs, and other agencies.

  • Evidence Evaluation:

    • Physical descriptions: opportunity, motive, means, modus operandi, and composite sketches.

    • Conducting interviews of families, friends, neighbors, and assessing witness behavior.

The Stage of GP Implementation

  • Data availability, computer systems, software, and printers are crucial.

  • Recognizing that crimes exhibit distinctive geographic patterns related to social problems.

Modelling Criminals’ Use of Space

  • Crime Occurrence and Opportunity

    • Offender decisions based on personal characteristics and opportunities.

  • Hull's Perspective

    • Learning through habits and routines; limited internal mental representations.

  • Tolman’s Theories

    • Development of cognitive maps; offenders have mental maps influencing their crime locations.

  • Two Key Concepts:

    • Propinquity: How close crime locations are to significant places in an offender's life.

    • Morphology: Geometry of crime distribution centered on the offender’s base.

Theoretical Frameworks of GP: Geocriminology

  • Focus on criminogenic environmental factors influencing crime likelihood.

  • Conceptual Clustering of Behaviors

    • Temporal and spatial behaviors are examined concerning personal narratives through propinquity and morphology.

  • Theories Related to GP

    1. Crime Pattern Theory (CPT)

    2. Routine Activity Theory (RAT)

    3. Rational Choice Theory (RCT)

Crime Pattern Theory (CPT)

  • Defined Concepts

    • Activity Space: An individual's engagement zone within their environment, shaped by experiences.

    • Nodes: Key locations involved in an individual's daily journey, where opportunities may arise.

    • Paths: Routes between nodes, critical for understanding where potential crimes may occur.

    • Edges: Boundaries where nodes and paths interact; often sites for crime due to the intersection of unknown individuals.

Routine Activity Theory (RAT)

  • Framework Description

    • The theory posits that legitimate daily activities influence the probability of encountering illegal activities.

    • Crucial Factors in Crime Occurrence:

    • A motivated offender

    • Availability of a potential target (victim)

    • Absence of a capable guardian.

Rational Choice Theory (RCT)

  • Explanation of Crime Decisions

    • Crime is approached as a systematic decision-making process, weighing potential costs against benefits.

    • Emphasizes rational behavior in the offender's choices:

    • Consideration of moral considerations and community impact.

Synthesis of Theories

  • How the three theories interconnect and inform Geographical Profiling.

Principles of GP Related to Propinquity & Morphology

  • Key Principles

    • Least-Effort Principle: Offenders choose actions requiring the least effort.

    • Journey to Crime: Offenders typically do not travel far from home to commit crimes.

    • Decay Function: The likelihood of crime decreases with increased distance from the offender’s home base.

    • Circle Hypothesis: A circle with a diameter equating to the distance between the two farthest crime locations may define the offender’s home base.

Criminal Range vs. Home Range

  • Definitions

    • Criminal Range: Area encompassing all offense locations, influenced by various factors like resources and familiarity.

    • Home Range: Region offenders typically do not offend outside of.

Mental Maps and Geographical Constraints

  • Personal mental maps guide offenders’ decision-making in their spatial activity.

  • Discussion of encoding information and interpretative understanding of surroundings via morphology.

Routes to Crime - Models

  • Commuter Model: Offenders commuting from home to crime sites, maintaining a distance from their home base.

  • Marauder Model: Offenders operate closer to home, often overlapping with both home and crime ranges.

Summary of Findings and Implications

  • Crime is systematically influenced; it is not random.

  • Both victims and offenders utilize space and time methodically.

  • Crime is often committed when daily routines intersect with opportunity.

General Findings from GP Studies

  • Emotional crimes often involve shorter distances traveled.

  • Data from case studies indicate serial offenders typically operate within familiar areas.

  • The range pattern of attacks is intertwined with crime familiarity and commuting factors.

Limitations of Geographical Profiling

  • Reduced accuracy with fewer links between crimes.

  • Not all offender types or crime categories can be effectively profiled geographically.

  • Cultural and environmental variations hinder uniform application of GP methodologies.

Application of GP Techniques and Technology

  • Computerized Geographic Profiling Systems (CGP)

    • Predicative tools that locate offender anchor points using distance-decay functions.

    • Examples of CGP:

    • Dragnet (Canter et al., 2000): A geographical prioritization package for offender base location prediction.

    • RIGEL (Rossmo, 2000): A comprehensive Geographic Profiling tool developed for police use.

    • CrimeStat (Levine & Associates, 2000): A free American tool for geographic crime mapping.

Considerations & Limitations of CGP Techniques

  • Implementation Challenges

    • Reliance on accurate crime location data and recording.

    • Cost and training requirements for law enforcement personnel.

  • Limited effectiveness when accounting for environmental variability and target distributions.

Man vs. Machine Debate in GP

  • Examination of effectiveness between computerized systems and heuristic-based predictions in GP.

  • Research suggests that heuristic predictions can be competitively accurate compared to expensive computerized solutions.

Closing Notes

  • Geographical Profiling serves solely as an investigative tool; it does not solve crimes on its own.

  • Questions about offender behavior related to travel distances and crime scenes can provide insights into profiling efforts.