This thesis addresses how uncertainty in forensic science can be conceptualised, evaluated, and communicated to lay stakeholders. Traditionally uncertainty has been articulated with vague definitions, while typologies of uncertainty have not been systematically and clearly established. The evaluation of uncertainty has largely been restricted within the confines of the Bayesian theorem and the methods and means of communicating uncertainty have yet to be agreed by the academic community and the criminal justice sector. The first study of the thesis reviews the current narrative within forensic science with regards to the conceptualisation of uncertainty, through an exploration of the definitions, typologies and characteristics recognised and used by academics, policymakers and the courts. An interdisciplinary configurative review was then conducted into three allied neighbouring disciplines of medicine, environmental science and economics, to identify innovative ways to conceptualise, evaluate and communicate uncertainty to lay stakeholders in forensic science. As a result, three toolkits were developed, one each for the three facets of addressing scientific uncertainty. A third study was then carried out, to establish the sources of uncertainty that key stakeholders identified to be priorities for evaluation and communication for the application of science to the justice system. This study thereby tested that the findings from the interdisciplinary systematic review reflected the experiences of stakeholders, and in so doing provided a foundation for optimising the value of the three toolkits. The wider implications of dealing with uncertainty in forensic science in a more consistent, coherent and standardised fashion are then considered with a focus on both the discipline itself, and for different stakeholders within the criminal justice system. There is a clear need to recognise uncertainty as a salient issue in every stage of the forensic science process, and particularly so in the presentation of forensic science evidence in court. The body of work presented here offers a starting point for the development of a more coherent and consistent understanding of scientific uncertainty in forensic science, while also encouraging fruitful conversations regarding ways through which it can be evaluated and communicated to lay stakeholders. This research identifies the key aspects of considering uncertainty as a fundamental and integrated part of forensic science by identifying the nuances, complexities and limitations of forensic science evidence in the context of the delivery and application of science in a multiple stakeholder justice system
