In this paper we introduce a permutation testing approach to the interpretation of evidence which consists of elemental composition measurements, with glass evidence as an example. This work extends previous work of Curran et al. [J.M. Curran, C.M. Triggs, J.R. Almirall, J.S. Buckleton and K.AJ. Walsh, The interpretation of elemental composition measurements from forensic glass evidence, Science and Justice 37 (1997) 241-244.] and shows how we may remove some of the constraints that limited the applicability of the previous results. We provide the reader with tools for evidence pre-screening that may aid in the direction of further analyses of the data, rather than for the presentation of evidence interpretation in a court case.