Crime can be measured in several ways, including police records, victimization surveys, and self-report surveys. The most widely used measures are police records, which have limitations in measuring crimes like assaults and robberies that are often unreported. Other approaches like the National Crime Victimization Survey provide data on both reported and unreported crimes to give a fuller picture of crime. No single measure captures all crime, so multiple methods are typically used to gain different perspectives.
2. •Crime can be a dependent variable in
exploratory, descriptive, explanatory, and
applied studies
•Crime can also be an independent variable, as
in a study of how crime affects fear and other
attitudes
•It can be both: drug use other offenses
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3. •What offenses?
•What units of analysis?
•Specific entities about which researchers collect
information
•Offender, victim, offenses, incidents
•What purpose?
•Monitoring
•Agency Accountability
•Research
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4. •Most widely used measures of crime are based
on police records
•Certain types are detected almost exclusively
by observation (traffic and victimless offenses)
•Most crimes reported by victim or witnesses
•What crimes are not measured well by police
records?
•Assaults
•Robberies
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5. •Circa 1929, under FBI since 1930s
•Originally, reporting voluntary, but now very
common
•Type I offenses (Index crimes/offenses):
murder, rape, robbery, larceny, burglary,
aggravated assault, motor vehicle theft and
arson (added in 1979)
•Type II offenses: a compilation of less serious
crimes
•Summary-based, group level unit of analysis
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6. •The UCR is neither an exclusive nor an
exhaustive measure
•Not all law enforcement agencies submit
complete reports to the FBI, and the quality of
the data submitted varies
•Summary-Based Measure of Crime
•UCR data includes summary, or total, crime counts
for reporting agencies (cities/counties)
•UCR data are aggregates - cannot be used in
descriptive or explanatory studies that focus on
individual crimes, offenders, or victims
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7. •Based on incidents as units of analysis
•Supplementary Homicide Reports (SHR)
•Police agencies submit detailed info about
individual homicide incidents
•Can conduct a variety of studies that examine
individual events
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8. •Joint effort by FBI and BJS to convert UCR to a
NIBRS
•NIBRS reports each crime incident rather than
the total # of certain crimes for each Law
Enforcement agency
•Many features are reported individually about
each incident, offenses, offenders, victims
UCR NIBRS
8 Part I offenses 46 Group A offenses
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9. •Hierarchy rule dropped
•Victim type (individual, business,
government, society/public)
•Attempted/Completed
•Drug-related offenses
•Computers and crime
•Quality control; states require certification
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10. •Eliminating the hierarchy rule means offense
classifications are mutually exclusive
•But not exhaustive, not all crimes are counted
•Creating auditing standards and requiring
submission of data on computer readable media
enhance reliability
•Crimes are selectively reported to police and
selectively recorded by police
•Voluntary: no agency is required to submit crime
reports to the FBI in any form
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11. •Can obtain info on crimes not reported to police
•Can measure incidents police may not officially
record as crimes
•Provides data on victims/offenders (individuals),
and the incidents themselves (social artifacts)
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12. •Since 1972 by Census Bureau
•Sought to illuminate the “dark figure of
unreported crime”
•Longitudinal panel study: households agree to
participated for 3 years (7 interviews; one every
6 months) and then replaced
•Does not measure all crime
•Respondents are asked screening questions
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13. •Measures both reported and unreported crime
•Independent of changes in reporting
•More information about how crime impacted
victim than UCR
•Provides more victim characteristics than UCR
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14. •Telescoping incident dates
•Faulty memory
•Little information on offenders
•No information on CJS response if reported
•Excludes crimes against commercial
establishments
•Only includes residents of US
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15. •Sought to improve measurement of domestic
violence and sexual assault
•Revised screening questions and added cues to
help respondents recall and distinguish minor
incidents
•More direct questions on rape and other sexual
crimes
•Greater attention to measuring victimizations
by someone the respondent knows
•Gradual increase of telephone interviews to
replace in-person interviews
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16. •First Development in late 1960’s
•A series of city-level surveys by the Census Bureau
•1998 BJS and the Office of Community Oriented
Policing Services (COPS) launched pilot surveys
in 12 large and medium-sized cities
•Jointly developed a guidebook and software so that
local law enforcement agencies and other groups
can conduct their own community surveys
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17. •Crimes Known to Police:
•UCR
•SHR
•NIBRS
•Victim Surveys
•NCVS
•Community Victimization Surveys
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18. •Delinquency, "victimless" crimes, and crimes
rarely observed or reported to police may be
measured by self-report surveys
•Example: prostitution, drug abuse, public order,
shoplifting, drunk driving
•Two ongoing self-report studies
•National Survey on Drug Use and Health (NSDUH)
•Monitor The Future (MTF)
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19. •Based on a national sample of households
•Conducted since 1971; 2004 sample had
68,000 individuals
•Includes questions to distinguish between
lifetime use, current use, and heavy use
•Encourages candid responses via procedures
•Includes residents of college dorms, rooming
houses, and homeless shelters
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20. •Conducted since 1975 by the National Institute
on Drug Abuse
•Includes several samples of high school
students and others, totaling about 50,000
respondents each year
•Questions concern self-reported use of alcohol,
tobacco, illegal drugs, delinquency, other acts
•A subset of 2,400 MTF respondents receive
follow-up questionnaire
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21. •Surveillance systems have been developed to
obtain alternative measures of drug use
•Arrestee Drug Abuse Monitoring (ADAM) –
provides ongoing assessment of drug use among
arrestees
•Drug Abuse Warning Network (DAWN) – collects
emergency medical treatment reports for “drug
episodes” from a sample of hospitals
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22. •Local Crime and Self-Report Surveys
•e.g., any purpose!
•Incident-Based Crime Reports
•e.g., Newark PD vehicle theft
•Observing Crime
•e.g., shoplifting, bar drinking and violence
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23. •UCR & SHR: best for murder and crimes in
which the victim is a business or commercial
establishment
•NCVS: best for crimes against persons or
households that are not reported to police
•Self-report surveys: best at measuring crimes
that do not have readily identifiable victims and
that are less often observed by or reported to
police
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