Unobtrusive measurement: using police information for forensic research

Abstract
This article explores how unobtrusive research methods popularized by Webb et al. (1966) can be utilized in forensic research. In particular, the value of the approach is considered with special reference to examining investigative processes and criminal behaviour. Webb et al.’s three non-reactive types of unobtrusive measures (physical traces, archival material and simple observation) are discussed in relation to a variety of types of material collected across the course of police enquiries. The breadth and variation of this material is emphasized with special consideration of its utility for research. We illustrate how the limitations and benefits identified by Webb et al. are echoed within the forensic domain and how close attention to the methods of collecting such material developed by researchers may improve the effectiveness of investigations.