 Few forms of evidence can speak directly to offense level hypotheses. Circumstantial evidence that is more amenable to a probabilistic quantification, such as DNA matches and other trace evidence, does not. Eyewitness testimony may speak more directly to offense level hypotheses, but it is also less easily amenable to a probabilistic quantification (see however Friedman 1987, recent results by Wixted and Wells 2017, and a survey of related issues by Urbaniak et al. 2020). This makes it difficult to assign probabilities to offense level hypotheses. Moving beyond source level hypotheses requires a close collaboration between scientists, investigators and attorneys (see Cook et al. 1998 for a discussion).