Proposals to limit Senate debate are as old as the Senate itself. Over the 216-year history of the body, numerous procedures have been proposed to allow the Senate to end discussion and act. The most important debate-limiting procedure enacted was the adoption in 1917 of the "cloture rule," codified in paragraph 2 of Senate Rule XXII. Under the current version of this rule, a process for ending debate on a given measure or matter may be set in motion following a super-majority vote of the Senate. Since the Senate's adoption of the cloture rule in 1917, proposals have been advanced to repeal or amend it in almost every session of Congress. At times, Senators of both political parties, as well as the parties themselves, have debated the merits of the Senate's tradition of free and unlimited debate and argued for and against making cloture easier to invoke. These debates occurred at different times and under different sets of circumstances, for example, as Senators attempted to prevent filibusters of civil rights measures, pass consumer protection legislation, or secure the confirmation of judicial or executive branch nominations. Debates on the cloture rule have frequently focused on whether or not the Senate must consider amendments to it under the body's existing rules, including Rule XXII itself. This argument rests on the principle that the Senate is a "continuing body" which regards its rules as staying in force from one Congress to the next. A contrary argument contends that this principle has the effect of "entrenching" the existing rules against change, a situation which amounts to an unconstitutional limit on the power of the body to set the terms of its own operation. To overcome these difficulties, Senators attempting to change Rule XXII have employed various procedural tactics, including seeking to invoke cloture by majority vote, seeking opinions by the Vice President acting as presiding officer that the cloture rule itself is unconstitutional, and arguing that the rules do not apply on the first day of a Congress. Although many attempts have been made to amend paragraph 2 of Rule XXII, only six amendments have been adopted since the cloture rule was enacted in 1917: those undertaken in 1949, 1959, 1975, 1976, 1979 and 1986. Each of these changes was made within the framework of the existing or "entrenched" rules of the Senate, including Rule XXII. In 1949, the cloture rule was amended to apply to all "matters," as well as measures, a change which expanded its reach to nominations, most motions to proceed to consider measures and other motions. A decade later, in 1959, its reach was further expanded to include debate on motions to proceed to consider changes in the Senate rules themselves. The threshold for invoking cloture was lowered in 1975 from two-thirds present and voting to three fifths of the full Senate except on proposals to amend Senate Rules. In a change made in 1976, amendments filed by Senators after cloture was invoked were no longer required to be read aloud in the chamber if they were available at least 24 hours in advance. In 1979, Senators added an overall "consideration cap" to Rule XXII to prevent so-called post-cloture filibusters, which occurred when Senators continued dilatory parliamentary tactics even after cloture had been invoked. In 1986, this "consideration cap" was reduced from 100 hours to 30 hours to meet the demands of a modern Senate whose proceedings were televised nationally. In its current form, which was adopted in 1986, Rule XXII provides that a cloture motion must be signed by 16 senators and presented on the Senate floor. One hour after the Senate meets on the second calendar day after a cloture motion has been filed and after a quorum has been ascertained, the presiding officer puts the question, "Is it the sense of the Senate that the debate shall be brought to a close?" The cloture motion is then subject to a yea-and-nay vote. If three-fifths of Senators—60 if there are no vacancies in the body—vote for the cloture motion, the Senate must take final action on the matter on which it has invoked cloture by the end of 30 total hours of additional consideration. Invoking cloture on a proposal to amend the Senate's standing rules requires a higher threshold, approval by two-thirds of the Senators present and voting, or 67 senators if there are no vacancies and all Senators vote. Once cloture has been invoked, the clotured matter remains the pending business of the Senate until it is disposed of and no Senator may speak for more than one hour. Senators may yield all or part of their allotted hour to a floor manager or floor leader, who may then yield time to other Senators. Each floor manager and leader, however, can have no more than two hours in total yielded to him or her. As with most Senate procedures, any of these requirements may be waived by unanimous consent. After cloture has been successfully invoked, no dilatory amendments or motions are permitted, and all debate and amendments must be germane. Only amendments filed before the cloture vote may be considered, and Senators may not call up more than two amendments until every other Senator has had an opportunity to do likewise. Printed amendments that have been available for at least 24 hours are not read when called up. Time for votes, quorum calls, and other actions is charged against the 30-hour limit on consideration. This time limit may be extended by joint leadership motion if three-fifths of all senators vote for a non-debatable motion to do so. Senators who have not used or yielded ten minutes of their hour are guaranteed up to ten minutes to speak. When all time expires, the Senate immediately votes on any pending amendments and then on the underlying matter. Concern by some Senators over an inability to halt debate and obtain a confirmation vote on several pending judicial nominations led to a renewed interest in the 108 th Congress and the 109 th Congress in amending the Senate cloture rule. In the 108 th Congress several resolutions were introduced on the subject. Proposals currently under discussion include: Media reports have focused on the possible use of what has been called a "nuclear" parliamentary option to end debate and vote on certain stalled nominations. Under such a scenario, the chair, perhaps occupied by the Vice President serving as Presiding Officer or by the President Pro Tempore of the Senate, would set aside the existing provisions of Rule XXII and rule that cloture could be invoked by simple majority vote. Supporters of such an approach argue that if such a ruling were appealed by opponents or submitted to the Senate for decision, and then sustained by a majority vote, debate would end and the pending business could then be brought to a vote. In another version of this scenario, a Senator might raise a constitutional point of order against the decision that cloture had not been invoked on a matter, and the same end achieved if the point of order were sustained by a majority vote of Senators. Supporters argue that this proceeding would be permissible because under the Constitution, the Senate has the express right to make, or change, the rules of its proceedings at any time. They further point out that such constitutional questions are traditionally submitted to a vote of the full chamber for decision. Under this latter scenario, however, the chair would likely have to also ignore the precedent that constitutional questions are debatable, perhaps by stating that the body has a right to "get to the question" at hand. Those concerned about the filibuster of judicial nominations have also argued that the inability of the Senate to reach a final vote on a nomination represents an abdication of the Senate's duty to perform a constitutional duty, that of advising and consenting to nominations. Majority Leader Bill Frist told his Senate colleagues on January 4, 2005, that he was willing to take steps to use one of the "nuclear" or "constitutional" options in the 109 th Congress, if he felt it was necessary. So let me say this: If my Democratic colleagues exercise self-restraint and do not filibuster judicial nominees, Senate traditions will be restored. It will then be unnecessary to change Senate procedures. Self-restraint on the use of filibuster for nominations—the very same self-restraint that Senate minorities exercised for more than two centuries—will alleviate the need for any action. But if my Democratic colleagues continue to filibuster judicial nominees, the Senate will face this choice: Fail to do its constitutional duty or reform itself and restore its traditions, and do what the Framers intended. Right now, we cannot be certain that judicial filibusters will cease. So I reserve the right to propose changes to Senate Rule XXII and do not acquiesce to carrying over all the rules from the last Congress. Opponents have used the term "nuclear" to describe these scenarios because of their belief that its use would destroy the comity and senatorial courtesy necessary in a body that operates largely by unanimous consent. They further argue that such an approach might destroy the unique character of the Senate itself, making it more like the House of Representatives, where a majority has the ability to halt debate any time it wishes. Observers point out that such a parliamentary proceeding is not unprecedented. On several occasions, Vice Presidents acting as presiding officer, including Vice Presidents Richard Nixon, Hubert Humphrey and Nelson Rockefeller, offered advisory opinions from the chair that the provisions of Rule XXII can be changed by a majority vote of the Senate at the beginning of a Congress. In 1975, a ruling to this effect, submitted to the chamber by Vice President Nelson Rockefeller, was sustained by a vote of the Senate. The Senate later reversed itself by recorded vote, but whether this obliterated the precedent permitting cloture by majority vote has been a source of disagreement.