Agency officials possess considerable discretion in rulemaking. At the front end, agency officials decide, in most cases, whether rulemaking is needed at all. During rulemaking, agency officials decide what processes must be followed, what rules govern those processes, and the timing of the various stages of the process. In the end, it is agency officials who review the evidence, find the facts, and draft the final rule.

However, this authority is not unchecked. All three constitutionally created governmental branches play a role in controlling the authority of administrative officials in rulemaking. The rulemaking procedure set forth in the APA is intended to limit the discretion of agency officials by mandating minimum rulemaking procedures. Congress can withhold from, or otherwise limit, the authority of an agency to make rules.

Congress controls agencies in various ways. Of course the greater authority Congress has is the creation, definition, and funding of agencies. Defining and refining its delegation of rulemaking authority is also an important control. Congressional delegation of rulemaking authority must be accompanied by an intelligible principle, a requirement aimed at limiting the pol-icy discretion of the receiving agency. In addition to controlling delegations of rulemaking authority, Congress has often attempted to control rules themselves.