Distinguishing stalking modus operandi: An exploration of the Mullen et al (1999) typology in a law-enforcement sample

Effective management of stalking cases relies upon distinguishing different forms of the offence. In the clinical context, Mullen et al's (1999) typology of stalkers is the most widely used classification system, the basis of the Stalking Risk Profile assessment tool. The present study explores the detailed patterns of stalking behaviour observed in a law enforcement context to explore the applicability of the Mullen et al clinical framework. Data are derived from 50 stalking cases obtained from the Threat Management Unit of the Los Angeles Police Department. Twenty-six offence variables were submitted to a Multidimensional Scaling Procedure, namely Smallest Space Analysis (SSA). Results showed that, as Mullen et al. posited, while some support for the incompetent and rejected types could be found, this clinical typology of stalkers did not hold in the law enforcement sample. An alternative framework for distinguishing detailed stalking offending styles and a common basis for understanding the development of these in an increasing intrusiveness is proposed.