Purity and contamination in online popular forensics: amateur-expert readings of the Meredith Kercher murder case

Abstract

This article examines online discourses of innocence and guilt in the Meredith Kercher murder case. One of its protagonists, Amanda Knox, sparked intense discussion across the entire mediascape. We discuss how the two principal online communities in this case deconstructed the forensics of a crime that has continued to divide both social and conventional mass media. Elaborating the concept of the amateur-expert which has echoes of crowdsourcing, fandom, communities of practice and self-help cultures, we argue that online engagement with forensics amounts to a particularly intense form of participation which is neither that of a professional nor that of the casual observer. As for the type of amateur-expert discourse that was produced in order to make sense of the Kercher murder, we observe how notions of purity and contamination, which constitute a prominent source of metaphors for cultural representations of innocence and guilt, purveyed the lexicon with which suspects' culpability and the probity of legal-forensic procedures were scrutinized by online forums.