We propose a revised definition of “argument scheme” that focuses on describing argumentative performances and normative assessments that occur within an argumentative context, the social context in which the scheme arises. Our premise-and-conclusion structure identifies the typical instantiation of an argument in the argumentative context, and our critical framework describes a set of normative assessments available to participants in the context, what we call _practically normative_ assessments. We distinguish this practical normativity from the _rationally or universally normative_ assessment that might (...) be imposed from outside the argumentative context. Thus, the practical norms represented in an argument scheme may still be subject to rational critique, and the scheme avoids the is/ought fallacy. We ground our theoretical discussion and observations in an empirical study of US district court opinions resolving legal questions about copyright fair use and the lawyers’ briefs that led to them, instantiating our definition of argument scheme in the “argument for classification by precedent.” Our definition addresses some criticisms the argument-scheme construct has received. For example, using our data, we show that a minimally well formed instance of this type of argument does not shift any conventional burden from the proponent of the argument to its skeptics. We also argue that these argument schemes need not be seen as dialogical. (shrink)