This paper approaches legal argumentation from a rhetorical perspective. It discusses the nature of the audiences that are targeted by judges in the legal process. Judicial opinions reach diverse groups of people with very different attitudes and expectations: other judges, lawyers, litigants, concerned citizens, etc. One important way in which these groups differ is that some of them are more likely to be persuaded by legalistic, precedent or statute-based arguments, while others expect judges to decide on grounds of justice or (...) equity. So, judges face the challenge of determining whether they should select particular groups for special attention, or whether they have alternative rhetorical means to approach the problem of audience diversity. One strategy that is likely to be recommended by rhetorical scholars is that judges should not try to accommodate the various preferences of their actual readership, but that they should rather invoke an idealized audience or some version of Chaïm Perelman’s universal audience. However, the paper tries to show that the universal audience is of limited value for a discussion about how judges ought to proceed in the face of audience diversity. In particular, the idea of a universal audience does not help judges to make the choice between a legalistic or an equity-based approach to legal decision-making. By showing that this is so, the paper also raises doubts about the common thought that to invoke the universal audience in law is to appeal to natural law. (shrink)