Basic Concepts CJS 380 Crime Science:Principles, Strategies and Practice of Crime Prevention and Reduction J.A. Gilmer
Crime Mapping Pioneers Pioneers in the Study of Crime and Place André-Michel Guerry(1802–1866) & Adriano Balbi(1782 –1848) Essay on the Moral Statistics of France (1832)
Pioneers in the Study of Crime and Place AdolpheQuetelet(1796-1874) Belgian mathematician and astronomer Applied statistical analysis to understanding crime relative to place (areas) and demographics Crime concentrated in areas of wealthy/educated & committed by poor/unemployed Propensity to commit crime Inequality as criminogenic factor Also developed “Body Mass Index” (BMI) still used today
‘Space’ and ‘Place’ in Crime Science “Space” – areas such as neighborhoods, census tracts, or larger territories Boundaries may be political or administrative, such as police precincts or districts, cities, etc. Often recognized from internal or cognitive frame of reference – a ‘mental map’ Defined by “sum of all places” within (Bourbon St) “Place” – smaller than a ‘space’ – house, business, street corner, etc.
Time and Temporal Analysis Time – how humans parse the continuity of being Time of day, Day of week, Monthly, Quarterly, etc. Temporal Analysis: study of crime in relation to time (and geography) Moments – when and where a crime occurred Exact timevs.Time span crimes Relative accuracy of occurrence as identified by victim Techniques for resolving: mid-point analysis, weighted method Duration – “how long event/process continued in specific space” Distance as Time – representation of physical space in temporal dimension -- “time to crime”
Crime Crime : Law ≈ Deviance : Norms (True or False) Penal Code vs. Code of Student Conduct Code of Hammurabi (Just Deserts??) “If a man puts out the eye of an equal, his eye shall be put out.” Substantive (Penal) and Procedural Law Penal Law applies to all members of the State Criminal Procedural Law regulates CJ actors
Counting Crime, Officially Calls for Service CAD systems – massive amounts of data with accurate temporal & geographic detail Citizen-initiated – CFS not always a crime “incident” Better measure of police activity than crime A biased measure of actual victimization Incident Data Based on reports from first-responding officers Subject to officer discretion No report, no crime????
Official Crime Statistics FBI Uniform Crime Reports (Summary UCR) Oldest and most widely implemented Classifies crime by seriousness into two parts Part I: Murder/manslaughter, Forcible rape, Robbery, Aggravated Assault, Burglary, Larceny/Theft, MV Theft, Arson Part II: Simple assault, possession/sale drugs, weapons possession, possession/sale stolen property, forgery and fraud, vandalism, disorderly conduct, etc. NYS Crime Data http://criminaljustice.state.ny.us/crimnet/ojsa/stats.htm
Limitations of UCR Crime Data Accuracy – ‘crimes reported to police’ no report, no crime??? Consistency – legal differences across states Reliability – can be manipulated by police Truncation – “hierarchy rule” reports only most-serious crime in a multi-crime event Completeness – due to submission deadlines
NIBRS – the “new” UCR Incident-based reporting (IBR) Details at incident-level provided on Crime Incidents and Arrests Victims and Offenders Able to handle multiple crimes per incident Links victim(s) and offender(s) at incident level Expensive for agencies to implement Not widely used – in NYS < 240 LEAs of ~600 Many larger agencies (NYPD, Buffalo, Rochester) opted to stay with summary UCR reporting
Counting Crime, Unofficially Local Surveys Issues with sample bias, accuracy, validity and reliability Expensive to do correctly National Crime Victimization Survey (NCVS) National sampling methodology of 50,000 households twice a year of persons over 12 years of age Redesign will produce subnational estimates Self Report Surveys Specific to project (no national estimates) Sampling bias (representativeness) often a weakness
Criminal Victimization in US Of 20 million crimes in 2009: 78% (15.6 million) property crimes 22% (4.3 million) crimes of violence 1% (133,000) personal thefts Serious Violent Crime Trend Serious violent crime includes rape, robbery, aggravated assault, and homicide. http://bjs.ojp.usdoj.gov/index.cfm?ty=tp&tid=9
Qualitative Techniques In-depth interviews Easy to administer (voice recorder) Rich source of detailed information on topic Difficult to analyze and compare across studies Participant Observation Immersion in real-world setting Good for “understanding” Ethical issues (depending on level of participation) Impossible to replicate