In recent years, a process involving the Senate’s “amendment tree” has been increasingly wielded by Senate leadership as a means to limit opportunity for Senators to offer amendments on measures on the Senate floor. For many observers of the Senate’s legislative process, the act of “filling” the amendment tree is a controversial – yet powerful – tactic by which the Majority Leader can control the content of bills and the legislative process.

The Senate is unique in often offering its members significant opportunity and flexibility to amend a measure on the floor. Generally, a measure being considered on the floor is open to amendment in two degrees – amendments to the text of the measure (an amendment in the first degree), and an amendment to that amendment (an amendment in the second degree). The amendments that can be in order at any one time depend on the form of the first amendment, and then the type and degree of subsequent amendments. The series of these amendments and “amendments to amendments” are the “limbs” on the amendment “tree.”

The amendment tree is “filled” when all amendments permitted by orders of precedence have been offered and are simultaneously pending. By precedent set by the Senate, once the “tree” is filled, further amendments cannot be offered until those which are pending are voted on.

How and why can a Majority Leader “fill” the amendment tree? Technically, any Senator – or group of Senators, should they be working together – may offer amendments in such a way to fill the tree. After all, Senate Rule XIX stipulates that the Senate’s presiding officer recognize the “Senator who shall first address him” – as such, Senators may offer amendments in the order that they obtain recognition, which in turn is the order they address the chair. It is conceivable that a single determined Senator could monopolize the amendment-offering process. However, as has become tradition through practice throughout much of the 20th century, priority of recognition is afforded to the Majority Leader if they seek recognition simultaneous to other Senators.

Because of this, a Majority Leader is guaranteed the ability and opportunity to fill an amendment tree if they repeatedly get recognized in turn to offer amendments to a pending measure. As a practical matter, because of the custom of granting the Majority Leader (or their designee) priority recognition, no other Senator can fill the amendment tree. To fill the tree, the Majority Leader offers first degree and second degree amendments until the amendment tree is full and their amendments must be voted on. Before that vote, however, the Majority Leader may file cloture pursuant to Rule XXII. If cloture is agreed upon, it locks the amendments in place, closes further debate on them, and forces non-germane amendments away.

There are several reasons why a majority leader might pursue the strategy of “filling the amendment tree,” to include:

  • Expediting Senate consideration of legislation by limiting the total number of amendments offered;
  • Instituting a measure of control over the sequence or subject of floor amendments offered;
  • Gaining advantage in negotiations of a unanimous consent request for further consideration of a measure;
  • Protecting vulnerable members of the same party from having to vote on controversial or politically challenging amendments.

The tactic has significant implications for Senate deliberations. First, it increases the power of the Committees and Committee leadership in deciding the content and scope of a piece of legislation. It can moderate Senators from the process of filing amendments in protest, or attaching “poison pills” to a measure in an attempt to defeat it.  For Senators who wish to offer amendments in good faith, they must secure the buy-in of the Majority Leader, lest they “fill the tree” before the amendment may be made. This entails significant negotiation and back-room agreement between leadership and a Senator for the Senator to substantively contribute in the process of Senate floor action.

Yet, conversely, the Majority Leader must assess risk in deciding to fill the amendment tree – as Senators may reject a bill if they feel they have not been given an adequate opportunity, as is their Senatorial prerogative, to offer amendment to a measure.

There have been both successful and unsuccessful attempts to circumvent a “filled” amendment tree. In 2009, Senator DeMint of South Carolina successfully suspended the provisions of rule XXII, including germaneness requirements, so that his amendment could be proposed and considered after Majority Leader Reid had filled the amendment tree and filed cloture. This move became routine procedure in the Senate until October 2011.

In October 2011, Senate Minority Leader Mitch McConnell attempted to use DeMint’s procedure to offer the “American Jobs Act” as an amendment to the Currency Exchange Rate Oversight Reform Bill – on which Senator Reid had filled the amendment tree. Senator Reid, however, raised a point of order against motions to suspend the rules after cloture is invoked. To do so, he called up Senator Coburn’s suspension of the rules amendment and then made a point of order that such suspension was a “dilatory motion” under Rule XXII – the rule states that “no dilatory motions… shall be in order.”

Senator Begich of Arkansas, presiding in the chair, held that the point of order was no sustained. Senator Reid appealed the ruling. The vote on upholding the ruling went to the Senate, which voted 48 to 51 – thereby setting a new precedent that motions to suspend the rules are not in order after cloture, pursuant to Rule XXII. Thus, Senator McConnell’s attempt to circumvent the filled amendment tree was unsuccessful – and any further attempts by Senators to use the suspension of the rules for such a purpose will fail, as well.