From 1953 to 1975, initiatives to reform Senate Rule XXII at the start of a new Congress were biennial rituals. They were instigated mainly by Senators in each party frustrated by the chamber's inability to enact certain legislation, such as civil rights measures, due to filibusters. The biennial focus on amending Rule XXII at the beginning of a Congress declined somewhat with the revisions made to Rule XXII in 1975—cloture was lowered from two-thirds of the Senators present and voting to three-fifths of the Senators chosen and sworn—and the changes made in 1979 and 1986 involving the length of post-cloture debate. However, senatorial interest in changing Rule XXII at the start of a new Congress—called the "constitutional option" by some—reemerged in the 2000s. At the beginning of the 112 th , 113 th , and 114 th Congresses—in 2011, 2013, and 2015, respectively—a number of reform-minded Senators unsuccessfully urged the Senate to adopt its rules on "opening day" by majority vote (as the House does on its first day) without having to mobilize a supermajority vote. For example, on January 6, 2015, a reform Senator stated: "It has been the tradition at the beginning of many Congresses that a majority of the Senate has asserted its right to adopt or amend the rules. Just as Senators of both parties have done in the past, we do not acquiesce to any provision of Senate rules—adopted by a previous Congress—that would deny the majority that right." Rule XXII mandates that prolonged debate on amendments to Senate rules can be brought to an end by a two-thirds vote of the Senators present and voting. Reform Senators have generally viewed the opening of a new Congress as a special constitutional time that permits the Senate to change its procedures by majority vote unencumbered by chamber rules adopted by a previous Congress. They cite the U.S. Constitution (Article I, Section 5) as their authority: "Each House may determine the Rules of its Proceedings," which implicitly means by majority vote, state the reformers. The two-thirds supermajority vote to invoke cloture on amendments to the chamber's rules effectively prevents the Senate from exercising its constitutional right to "determine the Rules of Its Proceedings." The reformers noted their "Catch-22" dilemma: How can the Senate amend Rule XXII when the practical effect of that rule is to prevent its amendment? Opponents reject the so-called constitutional option. They point out that the Senate has adopted rules, and the Constitution says nothing about the vote required to adopt those rules. They also emphasize that the Senate is a continuing body with continuing rules (the "continuing body" doctrine ). Their argument is essentially that a Senate majority (even a simple majority) can always amend the chamber's rules at any time during the two-year life of a Congress so long as the existing rules are observed, such as Rule XXII. Proponents of reform stress that the Constitution supersedes Senate rules. While they agree that a majority can amend Senate rules at any time, their concern is Rule XXII's two-thirds requirement to bring debate to a close on amendments to the chamber's standing rules. Such a high threshold has been viewed by some as an unconstitutional infringement on the right of a majority to amend Senate rules. To bolster their contention, reformers sometimes cite a 1957 advisory opinion by the President of the Senate, Vice President Richard Nixon. In response to a parliamentary inquiry, Nixon said: Any provision of Senate rules adopted in a previous Congress which has the expressed or practical effect of denying the majority of the Senate in a new Congress the right to adopt the rules under which it desires to proceed is, in the opinion of the Chair, unconstitutional. The Chair emphasizes that this is only his opinion, because under Senate precedents, a question of constitutionality can only be decided by the Senate itself, and not by the Chair. [U]ntil the Senate at the initiation of a new Congress expresses its will otherwise, the rules in effect in the previous Congress in the opinion of the Chair remain in effect, with the exception that the Senate should not be bound by any provision in those previous rules which denies the membership of the Senate the power to exercise its constitutional right to make its own rules. Given what appears to be renewed interest among a number of current lawmakers to amend Senate rules with only majority support at the start of a new Congress, it might be useful to proponents and opponents of this approach to review several considerations that suffused many of the earlier attempts (1953-1975). First a brief summary of ways to alter Senate rules. A conventional way to amend the chamber's rules is to have resolutions altering the standing rules referred to the Committee on Rules and Administration for hearings, markups, and possible floor consideration. Or the Rules and Administration Committee on its own authority could report to the floor legislation that amends the standing rules. Unanimous consent is another way to modify Senate rules. Still another is by statute, enacted pursuant to the chamber's constitutional rule-making authority. The Senate also can establish standing orders that are regulations or directives that are equivalent to a standing rule but are not incorporated into the standing rules. An example of a standing order is to designate the Senate Parliamentarian, upon his or her retirement, as "Senate Parliamentarian Emeritus." In addition, there is the so-called "nuclear option," which is "essentially a variant of the 'constitutional option.' The difference is that this parliamentary maneuver would be applied [during] a congressional session" rather than at the beginning of a new Congress. The term "nuclear" could be applied to both options in this specific sense: the success of either the constitutional or nuclear option might trigger a parliamentary meltdown, an explosion of dilatory and obstructive tactics by Senators who vehemently oppose limitations on their ability to debate at considerable length various measures or matters. The "nuclear option" involves the creation of a new Senate precedent that has the effect of preventing filibusters of specific measures or matters. In general, precedents are established in the following manner: Any ruling by the Chair in response to a point of order made by a Senator is subject to appeal. If no appeal is taken, the ruling of the Chair stands as the judgment of the Senate and becomes a precedent for the guidance of the Senate in the future.... [If there is an appeal, then unless] the Chair is supported by a majority vote of the Senate, the decision of the Chair is overruled. This decision of the Senate becomes a precedent for the Senate to follow in its future procedure until altered or reversed by a subsequent decision of the Chair or by a vote of the Senate. With respect specifically to the nuclear option, "some would hold that what would render proceedings 'nuclear' is not simply that they would establish new precedential interpretations of the rules, but that they would do so through proceedings that ... involve violations of procedural standards previously established and already in effect at the time the Senate is considering the proposed new interpretation." A key feature of precedential change is that the text of a formal rule remains unchanged, such as Rule XXII, but the new precedent effectively alters all or parts of its application and interpretation in chamber proceedings. As former GOP Senator Judd Gregg of New Hampshire emphasized, "In the parliamentary process, precedent is what controls." Attempts to amend Rule XXII involve two fundamental values that are in conflict: the right to debate versus the right to decide. The two can be reframed as minority protection versus majority rule. It can be quite difficult to reach an appropriate balance between these values when the Senate has before it controversial and contentious issues. There are no hard and fast rules regarding the length and thoroughness of debate. Many of today's complex, interconnected, and many-sided issues—cybersecurity, privacy, and so on—typically require extensive debate and involve the jurisdictional interests of several committees. In brief, barring broad consensus among Senators, it is usually difficult to amend Senate rules that affect the chamber's deliberative character. Noteworthy is that even the threat of extended debate—which today might be viewed as a "silent" filibuster—can stall action on various issues. Given a crowded Senate agenda, it may not be practical for majority party leaders to call up measures and spend considerable time (a scarce and precious resource) to try to end an expected talkathon. It is also not easy to determine the goals or motives of a Senator who engages in unending debate: Is it to thwart senatorial action on "bad" ideas, to highlight an urgent national issue, or to encourage the Senate to modify a measure? The point is that it is often difficult to define what constitutes a filibuster. As former Senator Robert C. Byrd, D-WV, the longest serving Senator in history, once said: "I will be able to perceive [a filibuster], because I know one when I see it." If an effort is made at the start of the 115 th Congress (2017-2018) to amend Senate rules by majority vote—the so-called constitutional option—what key concerns might Senators on either side of the issue bear in mind? Earlier attempts to alter Rule XXII suggest several considerations for Senators contemplating use of the constitutional option at the start of a new Congress. They are the support of the presiding officer, which could be the President of the Senate; the assistance of the majority leader; the mobilization of a determined and united majority; skillful use of procedural moves and countermoves; the length of "opening day"; the continuing body doctrine; and procedures to be followed pending approval of new rules. The historical record indicates that rulings from the Chair can either help or hinder the objectives of Senate reformers. In 1957, 1959, and 1961, Senate President Nixon propounded several advisory opinions that benefited the reformer's cause.