According to a common view, criminal law should be structured in a way that allocates the conditions of criminal liability to different types of legal rules, given the content of the condition and the nature of the rule. This view classifies some conditions as elements of offenses and others as (part of) justificatory defenses or of excusatory defenses. While this view is attractive, I argue that it should be rejected, since it is incompatible with two plausible propositions about legal rules. (...) The first is that foundational reasons are not concerned with the structure of the law as such. The second is that legal rules should be constructed in a way that reflects (the balance of) all the applicable reasons and not just some of them. (shrink)