Offence Definitions in the European Sourcebook of Crime and Criminal Justice Statistics and Their Influence on Data Quality and Comparability

Reaching a high conformity of reported data for different offence groups with the standard definitions provided for these offences is a crucial issue in order to improve comparability of crime and criminal justice data from official sources between countries. Based on data and metadata collected for the European Sourcebook of Crime and Criminal Justice Statistics (ESB), this article takes a close look at the offence definitions used in the 4th edition Sourcebook. After an overview on ESB methodology, namely on questionnaire design and data validation procedures, the general structure of offence definitions in the ESB context is shown and changes compared to earlier editions are explained. Afterwards, ESB data and definition metadata are used to check the quality of the definitions used. Overall and item conformity rates for each offence definition are calculated and assessed. Missing data rates as another indicator for quality problems of definitions are also evaluated. Then, variation coefficients for the different offence groups are compared and critically assessed. The final part of the article contains a view on the distribution of conformity with definitions across Europe. Altogether, offence definitions in the ESB turn out to work very well. Conformity rates tend to be high and variation coefficients are mostly quite uniform for the different offence categories. However, some problematic offence definitions can be identified. As a result of regional analysis it can be shown that conformity rates across Europe do not vary randomly, but follow a certain pattern.