In this essay, I consider how a legislature's rules of procedure can affect both the process and the outcome of legislation. By legislative rules of procedure I mean both the standing orders the legislature may establish for itself and those statutory or constitutional provisions that materially affect the legislature's processing of bills. The discussion is divided into two main parts.

First, I consider whether or not rules of procedure should have any effects at all, given that they can often be changed by simple majorities of legislators. One way that this concern can be expressed is in terms of policy instability. In multidimensional spatial models of legislative decision making under pure majority rule, the generic result is instability – that is, there almost never exists a policy that cannot be defeated in a pairwise majority vote by some other policy. Riker has argued that rules are valued primarily for their anticipated effect on policy outcomes, so that generically there will be no stability in the choice of rules, just as there is none in the choice of policies. By this argument, one cannot point to the rules as playing any systematic role in determining legislative outcomes.