The retrospective detective. Cognitive bias and the cold case investigator

Current research on police psychology in criminal investigations assumes investigative decision-making in cold case (undetected) homicides to be the same as that of live/current homicide investigations, therefore not warranting exploration in its own right. In contrast, the present article suggests that significantly different psychological and contextual factors exist which can facilitate bias in investigator decision-making in cold case (undetected) homicides. These include the biasing effect of inheriting a chain of decisions often made by many previous investigators and the negative framing effect that the term ‘cold case’ can have on investigator confidence and on their subsequent investigative decision-making. Although the idea that cold case homicide investigation necessitates a different ‘investigative mindset’ to live cases is only suggested here, a possible agenda for a bespoke research project on cold case investigator decision-making is tentatively suggested.