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Methods of Measuring CrimeMethods of Measuring CrimeMethods of Measuring CrimeMethods of Measuring Crime

Uniform Crime ReportsUniform Crime Reports

Self- Report SurveysSelf- Report Surveys

Victim SurveysVictim Surveys

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Uniform Crime ReportsUniform Crime ReportsUniform Crime ReportsUniform Crime Reports

Based on Crimes Reported to the PoliceBased on Crimes Reported to the Police

Based on a population unit of 100,000 peopleBased on a population unit of 100,000 people

Divided into two representativeDivided into two representativecategories: Indexed and non-Indexedcategories: Indexed and non-Indexed

Reported for U.S., Cities, and SMSA’sReported for U.S., Cities, and SMSA’s

Crimes known / Arrest = Clearance RateCrimes known / Arrest = Clearance Rate

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Uniform Crime ReportsUniform Crime Reports

► Part I “Index” CrimesPart I “Index” Crimes Criminal HomicideCriminal Homicide Forcible RapeForcible Rape RobberyRobbery Aggravated assaultAggravated assault BurglaryBurglary Larceny/theftLarceny/theft Motor vehicle theftMotor vehicle theft ArsonArson

► Part II CrimesPart II Crimes All others except trafficAll others except traffic

ViolentViolent Crime Crime

Non-violentNon-violentCrimeCrime

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Criticisms and Limitations of Criticisms and Limitations of the UCRthe UCR

Criticisms and Limitations of Criticisms and Limitations of the UCRthe UCR

Cannot capture the “dark figure” of crimeCannot capture the “dark figure” of crime

Methodological HiccupsMethodological Hiccups

• Counting RuleCounting Rule

• Reporting PracticesReporting Practices

• Attempted vs. Completed Attempted vs. Completed CrimesCrimes

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The Future of the Uniform The Future of the Uniform Crime ReportsCrime Reports

►National Incident-Based Reporting National Incident-Based Reporting System (NIBRS)System (NIBRS)

►Maintained by the F.B.I.Maintained by the F.B.I.►Twenty-two crime categoriesTwenty-two crime categories►More information on each crime in More information on each crime in

each categoryeach category►Data compiled based on incidents, Data compiled based on incidents,

not arrests.not arrests.

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Self-Report SurveysSelf-Report Surveys

Participants (usually juveniles) reveal Participants (usually juveniles) reveal information about their violations of the lawinformation about their violations of the law

AdvantagesAdvantages Helps to get at “Dark Figure of Crime”Helps to get at “Dark Figure of Crime” Tap into “victimless crimes”Tap into “victimless crimes” Make comparisons with “official data”Make comparisons with “official data” Only way to measure theoretical concepts Only way to measure theoretical concepts

and connect with criminal behaviorand connect with criminal behavior

Participants (usually juveniles) reveal Participants (usually juveniles) reveal information about their violations of the lawinformation about their violations of the law

AdvantagesAdvantages Helps to get at “Dark Figure of Crime”Helps to get at “Dark Figure of Crime” Tap into “victimless crimes”Tap into “victimless crimes” Make comparisons with “official data”Make comparisons with “official data” Only way to measure theoretical concepts Only way to measure theoretical concepts

and connect with criminal behaviorand connect with criminal behavior

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Self-Report SurveysSelf-Report Surveys

►DisadvantagesDisadvantages May underestimate “chronic May underestimate “chronic

offenders”offenders” People Can LiePeople Can Lie Survey Methodology ProblemsSurvey Methodology Problems

►Seriousness of OffenseSeriousness of Offense

Self-Report Surveys

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National Crime Victimization

Survey

1. Asks victims about their encounters with1. Asks victims about their encounters with criminals criminals2. Nationally representative sample2. Nationally representative sample3. May also describe people most at risk 3. May also describe people most at risk 4. Limitations:4. Limitations:

Little information about offendersLittle information about offendersCannot assess some crimesCannot assess some crimesLimitations of Survey Research Limitations of Survey Research

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REVIEWREVIEW

►UCRUCR Aggregate Data, Crimes known to policeAggregate Data, Crimes known to police

►Self-reportSelf-report Individual level data, links offender Individual level data, links offender

characteristics to criminal offendingcharacteristics to criminal offending

►NCVSNCVS Aggregate Data, victimizationsAggregate Data, victimizations

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Crime Trends and Crime Trends and Correlates of CrimeCorrelates of CrimeCrime Trends and Crime Trends and

Correlates of CrimeCorrelates of Crime►Crime TrendsCrime Trends

Is crime increasing, decreasing or stable?Is crime increasing, decreasing or stable? Why?Why?

►Correlates of CrimeCorrelates of Crime What factors are related to crime?What factors are related to crime? Geographic location, Age, Race, Gender, Geographic location, Age, Race, Gender,

Social Class?Social Class?

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Crime TrendsCrime Trends

►UCR and NCVS data reveal a recent UCR and NCVS data reveal a recent steady decrease in violent crime. steady decrease in violent crime. The decrease is being driven by a sharp The decrease is being driven by a sharp

decline in violent crime among juveniles.decline in violent crime among juveniles.

►NCVS indicates a long term trend of NCVS indicates a long term trend of decreasing property crimedecreasing property crime

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Duluth Violent Crime 1986-Duluth Violent Crime 1986-20002000

0

20

40

60

80

100

120

HomicideRapeRobbery

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Explaining Crime TrendsExplaining Crime TrendsExplaining Crime TrendsExplaining Crime Trends

Age Composition Age Composition The EconomyThe Economy Social malaiseSocial malaise Guns—Availability Guns—Availability Justice Policy—Police or Justice Policy—Police or

Prisons?Prisons?

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Social Class and Crime Social Class and Crime

►Official statistics reveal a strong class-Official statistics reveal a strong class-crime relationship.crime relationship. Lower Social Class more crime prone?Lower Social Class more crime prone? Criminal Justice System bias against the Criminal Justice System bias against the

lower class? (More likely to lower class? (More likely to arrest/prosecute?)arrest/prosecute?)

SELF REPORT STUDIES

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GENDER AND CRIMEGENDER AND CRIME

►UCR, NCVS, and SR data all indicate UCR, NCVS, and SR data all indicate that females are more likely than that females are more likely than males to commit criminal actsmales to commit criminal acts Chivalry hypothesis?Chivalry hypothesis? Socialization?Socialization? Biological differences?Biological differences? Feminist explanationsFeminist explanations

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RACE AND CRIMERACE AND CRIME

►Similar dilemma as with social classSimilar dilemma as with social class SRSRweak if any relationshipweak if any relationship OfficialOfficialstrong relationshipstrong relationship

► Is relationship due to bias?Is relationship due to bias? How police patrol and interact with minoritiesHow police patrol and interact with minorities Disparity in how CJS processes minorities? Disparity in how CJS processes minorities?

► If relationship is “true,” why?If relationship is “true,” why? Relationship to class, neighborhood, culture.Relationship to class, neighborhood, culture.

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0

500

1000

1500

2000

2500

Arr

est

Rat

e p

er 1

00,0

00

10 12 14 16 18 20 22 24 26 28

Age

ViolentProperty

The Age-Crime CurveThe Age-Crime Curve

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AGE AND CRIMEAGE AND CRIME

►Problems with the age crime Problems with the age crime curve:curve: Arrests onlyArrests only Aggregate dataAggregate data

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Longitudinal Birth Cohort Longitudinal Birth Cohort ResearchResearch

Longitudinal Birth Cohort Longitudinal Birth Cohort ResearchResearch

Research that tracks an identifiablegroup of individuals over a long periodof time.

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After following a birth cohort of 9,945 boysborn in Philadelphia in 1945, Wolfgang and his associates found that 6% of the total samplewere responsible for 51.9% of all offenses.These were referred to as chronic offenders orcareer criminals. Similar research has resultedin similar findings.

The “Chronic 6%”The “Chronic 6%”The “Chronic 6%”The “Chronic 6%”

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Continuity of CrimeContinuity of CrimeContinuity of CrimeContinuity of Crime

The cohort follow-ups clearly show that most chronic juvenile offenders continue their law-violating careers as adults.

The cohort follow-ups clearly show that most chronic juvenile offenders continue their law-violating careers as adults.

Then and ………….. NOW Then and ………….. NOW

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Implications of Implications of Continuity Continuity Implications of Implications of Continuity Continuity

If the “Onset” of offending occurs If the “Onset” of offending occurs in childhood for some kids, you in childhood for some kids, you must start your explanation at that must start your explanation at that point.point.

Why do some kids begin their Why do some kids begin their offending in adolescence? offending in adolescence?