In administrative law, it is generally assumed that once an agency promulgates a final rule, its work on that project—provided the rule is not litigated—has come to an end. In order to ensure that these static rules adjust to the times, therefore, both Congress and the White House have imposed a growing number of formal requirements on agencies to “look back” at their rules and revise or repeal ones that are ineffective.
Our empirical study of the rulemaking process in three agencies (N = 462 revised rules to 183 parent rules) reveals that—contrary to conventional wisdom—agencies face a variety of incentives to revise and update their rules outside of such formal requirements. Not the least of these is pressure from those groups that are affected by their regulations. There is in fact a vibrant world of informal rule revision that occurs voluntarily and through a variety of techniques. We label this phenomenon “dynamic rulemaking.” In this Article, we share our empirical findings, provide a conceptual map of this unexplored world of rule revisions, and offer some preliminary thoughts about the normative implications of dynamic rulemaking for regulatory reform.