A guide for the validation of DNA based species identification in forensic casework

Abstract

Method validation is an essential step ahead of applying a method in forensic casework, to ensure the results will be admissible in court. However, unlike mainstream forensic disciplines, wildlife forensic labs often evolve from conservation-oriented units and may not have a strong foundation in generating data within a legal context. As such, the processes and principles of method validation may not be familiar or fully understood. In this paper we describe the process of method validation in a wildlife forensic science context. We provide guidance on the documentation required to take a DNA based method, which has been developed to identify a specific target species, through the validation process so that it is fit for use in forensic casework. This process has been agreed upon among members of the Society for Wildlife Forensic Sciences (SWFS) Technical Working Group (TWG) to illuminate the requirements for both practitioners and academics.