An Original Methodological Contribution to Measuring Organised Crime Prevalence in Nigeria

Measuring organised crime prevalence is among the most methodologically challenging problems in criminology, and developing an original measurement methodology adapted to the Nigerian context, where conventional survey and police statistics approaches face unique validity threats, constitutes an important scholarly contribution. This study developed an original methodology for measuring organised crime prevalence across five organised crime categories in Nigeria: oil theft syndicates, drug trafficking organisations, advance fee fraud networks, kidnapping enterprises, and political electoral violence organisations. A methodology development approach employing multi-phase research design was adopted. Phase one conducted a systematic review of organised crime measurement methodologies from 28 international studies, identifying conceptual, measurement, and validity challenges. Phase two developed a multi-indicator triangulation methodology drawing on capture-recapture statistical methods, expert elicitation using the Delphi technique with 30 specialists, network size estimation from court records and media incident databases, and community victimisation survey proxies. Phase three validated the methodology through application to oil theft in Rivers State as a test case. The methodology produced an oil theft syndicate active participant estimate of 12,400 to 18,700 individuals in Rivers State, compared with 2,340 prosecuted cases in the EFCC database for the same period, confirming a prosecution-to-prevalence gap factor of 5.3 to 8.0. The original Multi-Indicator Organised Crime Prevalence Methodology (MIOCPM) constitutes a significant original methodological contribution and is recommended for adoption by the Nigerian Organised Crime Response Unit.

Keywords: organised crime measurement, methodology, Nigeria, original contribution, crime prevalence