8 October Case Updates Clarifying the role of validity testing in expert evidence 10. Records Assessments and Site Visits, Validity testing, Performance Validity Tests, Symptom Validity Tests Following last month’s case update by Professor Keith Rix of Brown v Morgan Sindall, several experts have offered further reflections on the use of validity testing in medico-legal assessment. Commentaries from Professor Michael Kopelman (neuropsychiatry), Dr Karen Addy (neuropsychology), Mr Daniel Friedland (neuropsychology) and Dr Kathryn Newns (clinical psychology) were published in the MAEP Expert Witness Healthcare Matters newsletter, coordinated by Professor Rix. This follow-up brings together the key points emerging across disciplines. It also clarifies several areas regarding the early learning points given in the September case update. The discussion in this article refines those conclusions and reflects current multidisciplinary consensus.