How is it that judgments, written by legal specialists, can withstand criticism from technical experts, such as scientists, accountants, medical practitioners and epidemiologists, with respect to the incorporation of expert evidence? Expressed more abstractly: why don’t concerns about accuracy and truth—what we might call the rule of fact—displace the range of rights, procedures and values conventionally associated with the rule of law? This chapter offers some tentative explanations. My general contention is that by maintaining responsibility for the interpretation of laws and procedures, and the ultimate resolution of disputes, judges are able to qualify, insulate, influence and control the ways in which expertise is received and understood throughout the legal system, its shadowlands and occasionally beyond. This chapter endeavors to examine some of the techniques, strategies and institutional arrangements which enable judges to mediate the influence of law and fact as well as protect their decision-making from exogenous critique.