The Senate uses a complex assortment of standing rules, statutory rules, standing orders, and precedents to regulate its debates. Senators have used these procedural mechanisms differently over time. For example, the Senate presently relies primarily on statutory rules to regulate the budget process. And senators increasingly rely on precedents to regulate their debates when the rules are ambiguous and when they are not. For example, senators may use the so-called nuclear option to create a precedent that is inconsistent with the Senate’s rules but nevertheless supersedes them.

Senators’ reliance on precedent to regulate their debates is evident in the growing influence of the Senate’s parliamentarian in recent decades. The Senate designated Charles L. Watkins as its first official parliamentarian on July 1, 1935. Prior to 1935, the Senate’s journal clerk provided “reliable and expert coaching” to help senators adjudicate points of order. The journal clerk used collections like Gilfry’s Precedents to advise senators on how the Senate interpreted its rules in the past. Yet those senators – unlike most of their present-day counter-parts – were not wholly dependent on the journal clerk when they adjudicated points of order.

There are several reasons why senators’ procedural independence declined beginning in the 1930. For example, New Deal legislation packed the Senate’s agenda and its members were spending less time on the floor beginning in this period. And the decline in senators’ familiarity with the rules has persisted to the present day.

As a result of that decline, the Senate’s parliamentarian became central to ensuring the orderly flow of legislation through the chamber. For example, former parliamentarian Floyd Riddick noted in the 1970s that the parliamentarian’s primary responsibility is to advise the presiding officer “on every procedure that he must rule on or everything he should say even.” In this capacity, senators understood parliamentarians to – in essence – preside over the chamber. When the presiding officer is prompted to respond to a senator’s parliamentary inquiry or make a ruling on a senator’s point of order, the parliamentarian presently advises him or her of the appropriate procedure. According to Riddick, the parliamentarian “tries to keep the Chair posted on each step of the procedure before it arrives, if he can stay ahead; or if it’s too complex and he can’t be ahead, sometimes he has to whisper one sentence at a time to be sure that the Chair states what the procedure is.”

The Senate’s customary practice of rotating junior senators in the majority party to preside temporarily over the chamber encourages their dependence on the parliamentarian. These senators are likely to be unfamiliar with the Senate’s rules and, therefore, likely to rely on the parliamentarian for advice on what to say when one of their colleagues asks a parliamentary inquiry or makes a point of order.

Dependence on the parliamentarian is not limited to the presiding officer. Individual senators and their staff also rely on the parliamentarian’s advice when crafting legislative proposals and planning parliamentary tactics in committees and on the floor. For example, staff will typically visit the parliamentarian’s office on the first floor of the Capitol (Senate wing) to pre-clear their senators’ proposals or tactics. Doing so benefits both the staff and the parliamentarian. The parliamentarian gets advance notice of potential procedural questions with which they may be confronted on the Senate floor. Such notice allows the parliamentarian to prepare for any relevant points of order that may arise by researching their procedural history. In general, individual senators (and their staff) receive expert advice on how to execute their efforts in compliance with the Senate’s rules and practices.