The question addressed here is whether evidence concerning defendants' past criminal records should be introduced at their trials because such evidence reveals their character and thus reveals whether they are the kinds of persons likely to have committed the crimes with which they are currently charged. I strongly caution against the introduction of such evidence for a number of reasons. First, the link between defendants' past criminal records and claims about their standing dispositions to think and act is tenuous, at best. Second, noncharacter, or trace, evidence should have primacy in determining the guilt or innocence of defendants. Third, character evidence will vary in its freshness and specificity. Other things being equal, only relatively fresh and specific character evidence has probative value. Moreover, such evidence will have greater probative value in criminal cases where the issue before the court is whether a crime has been committed than in cases where the issue is whether it was the defendant who committed the crime. Finally, we might be more sanguine about the introduction of fresh and specific character evidence under conditions likely to work against its misuse or misinterpretation. However, the relevant conditions may not often be satisfied in the real world of criminal trials and defendants.

In this article I criticize a theory of political obligation recently put forward by Christopher Wellman. Wellman's “samaritan theory” grounds both state legitimacy and political obligation in a natural duty to help people in need when this can be done without unreasonable cost. I argue that this view is not able to account for some important features of the relation between state and citizens that Wellman himself seems to value. My conclusion is that the samaritan theory can be accepted only if we are ready to give up either the traditional notion of political obligation as a prima facie duty valid for every citizen or the current view of the relationships that should exist between states, citizens, and foreigners (the view according to which states should have special concerns for their own citizens).

Elaborating first upon H. L. A. Hart's distinction between imposing duties and imposing disabilities, this article explores the two senses mentioned (but not fully explained) by Hart in which power-holders may be legally disabled. Legal invalidation (nullification) of norms that have been generated by vulnerable power-holders is seen to reduce diversity or pluralism in every normative sphere, from the supranational to the intrafamilial. By contrast, mere legal nonvalidation (noncognizance) of such norms tends to preserve the autonomy of the power-holders that created the norms, thus enhancing legal pluralism. Punishment for creating forbidden norms amounts in principle to an in-between sort of control, less restrictive than completely invalidating them but more restrictive than just not validating them, that is, just ignoring them. Illustrative examples include the European Court of Justice's early use of invalidation to convert an international treaty into a supranational constitution, and the subtle effects of legal nonvalidation of same-sex marriage.