Abstract
More and more, judges and juries are being asked to handle torts and other cases in which establishing liability involves understanding large bodies of complex scientific evidence. When establishing causation is involved, the evidence can be diverse, can involve complicated statistical models, and can seem impenetrable to non-experts. Since the decision in Daubert v. Merril Dow Pharms., Inc.1 in 1993, judges cannot simply admit expert testimony and other technical evidence and let jurors decide the verdict. Judges now must rule on which experts are admissible and which are inadmissible, and they must base their ruling at least partly on the status of the scientific evidence about which the expert will testify.2 This article is intended to provide judges with an accessible methodological overview of causal science.