1. CSCI 130 Forensic Computing CJ Notes Sources of Crime Data

2. I.Uniform Crime Reports I.Uniform Crime Reports a. Official crime data a. Official crime data b. Obtained via crimes reported to police b. Obtained via crimes reported to police c. FBI is national repository for crime; responsible for collecting and disseminating reports c. FBI is national repository for crime; responsible for collecting and disseminating reports d. Collects incidence data d. Collects incidence data e. Limitations e. Limitations 1. not all crime reported to police 1. not all crime reported to police 2. agencies may be bias data in how they classify offenses 2. agencies may be bias data in how they classify offenses 3. Part II offenses only report arrests 3. Part II offenses only report arrests

3. II. National Criminal Victimization Survey (NCVS) II. National Criminal Victimization Survey (NCVS) a. Begun in 1973 as NCS a. Begun in 1973 as NCS b. Bureau of Census survey sample of citizens as to their victimization experiences over the past six months b. Bureau of Census survey sample of citizens as to their victimization experiences over the past six months c. Measures victimizations of persons in household 12 yoa and older c. Measures victimizations of persons in household 12 yoa and older d. Asks if offence reported to police; if not, why not d. Asks if offence reported to police; if not, why not e. Limitations e. Limitations 1. does not measure crimes where victim <12 yoa 1. does not measure crimes where victim <12 yoa 2. does not measure homicides 2. does not measure homicides 3. does not measure commercial house robberies; bank robberies 3. does not measure commercial house robberies; bank robberies 4. does not measure burglaries 4. does not measure burglaries

4. III.Self-Reports III.Self-Reports a. Ask persons about their criminality or deviance a. Ask persons about their criminality or deviance b. Offender directed b. Offender directed c. Surveys of juveniles in schools; detentions houses; inmates; citizens at large c. Surveys of juveniles in schools; detentions houses; inmates; citizens at large d. May be biased as respondents over- estimate or under estimate activity d. May be biased as respondents over- estimate or under estimate activity e. Ethnographies are a type of self-report; anthropology heritage e. Ethnographies are a type of self-report; anthropology heritage

5. f. Use of informants to gain first-hand knowledge of behavior; lifestyle (early heroin user/addict research) f. Use of informants to gain first-hand knowledge of behavior; lifestyle (early heroin user/addict research) g. “Snowball” technique, where investigator is introduced to an addict, who in turn introduces the investigator to another and so on g. “Snowball” technique, where investigator is introduced to an addict, who in turn introduces the investigator to another and so on h. Allows investigators to study/learn about offenders in ways not possible with UCR or NCVS h. Allows investigators to study/learn about offenders in ways not possible with UCR or NCVS