This article seeks to account for the recent explosion in the use of expert legal evidence given by criminal law academics in criminal trials in Indonesia. This issue has received almost no scholarly attention, despite experts sometimes even opining on the guilt or innocence of defendants. Focusing on the evidence given for criminal trials by three preeminent Indonesian legal scholars, this article examines the form and content of the evidence, the justifications put forward in Indonesia for allowing it, and whether judges are receptive to it. Contrary to the assumptions of lawyers, we find that, overall, expert evidence appears to have very little discernible impact on judicial decision-making. It does, however, give the state an evidentiary advantage over defendants in some cases. We then consider what our findings say about the Indonesian judicial system—particularly the perceived competence of its judges—and the legal system more broadly.