p-Values should not be used for evaluating the strength of DNA evidence

Recently, p-values have been suggested to explain the strength of a likelihood ratio that evaluates DNA evidence. It has been argued that likelihood ratios would be difficult to explain in court and that p-values would offer an alternative that is easily explained. In this article, we argue that p-values should not be used in this context. p-Values do not directly relate to the strength of the evidence. The likelihood ratio measures the strength of the evidence, while the p-value measures how rare it is to find evidence that is equally strong or stronger, which is something fundamentally different. In addition, a p-value is not always unambiguous. To illustrate our arguments, we present several examples from forensic genetics.