The Senate is a pale imitation of what it once was.

A major reason for its current predicament is that senators are no longer freely able to amend the bills they consider. This is because the majority leader routinely blocks members from offering their own ideas on the Senate floor by filling the amendment tree.

While the tactic effectively precludes votes on unwanted amendments, the minority may still filibuster the underlying legislation in protest. This gives Senate minorities leverage to negotiate with the majority over what amendments will be permitted during a bill’s consideration, so long as 41 of its members are committed to blocking cloture until their demands are met.

But remaining united in opposition to cloture is not always easy, because the minority comprises individual senators who hold an array of policy views. Given this, the majority leader will negotiate directly with those members whose policy views are closest to his own when trying to secure the votes needed to invoke cloture.

The majority leader also can structure an amendment’s consideration in a way that makes its success less likely. This is done by setting a higher threshold for the amendment’s adoption in the unanimous consent agreement that typically schedules the vote on it. The utility of this approach to Senate majorities is reflected in the dramatic increase in its use in recent years to set 60-vote thresholds for passing amendments.


The earliest documented use of such a consent agreement occurred in the 102nd Congress. But it was a rare procedural tool until the 109th and 110th Congresses, when Majority Leaders Bill Frist, R-Tenn., and Harry Reid, D-Nev., respectively, began utilizing them on an increasing scale. In the 109th Congress, consent agreements were used in this manner in six instances. However, in the 110th Congress, their use increased significantly, totaling 37 instances. The use of the tactic remained relatively level in the 111th Congress at 38. In the 112th Congress, 60-vote thresholds were set on amendments on a staggering 111 occasions.

The tactic was utilized 35 times in the 113th Congress. The decline in amendments subject to a 60-vote threshold from the 112th to the 113th Congress is not as abrupt when viewed as a percentage of all amendments offered. This is because only 542 amendments were offered to legislation on the Senate floor during the 113th Congress (compared to 974 in the 112th).

Moreover, the share of roll call votes (RCVs) on amendments set at 60 by consent has increased since the 109th Congress. The routine utilization of the 60-vote threshold is particularly striking when RCVs on amendments to the budget resolution and reconciliation bills are omitted. Excluding budget and reconciliation amendments from the count yields a more accurate portrayal of the tactic’s centrality to decisionmaking in the Senate at present, because a member cannot be blocked, in theory, from offering amendments during the budget process’s vote-a-rama.


Pursuant to these unanimous consent agreements, the amendment is withdrawn if it does not get the requisite number of votes. The practice thus allows an amendment’s supporters to demonstrate support for cloture without going through the time-consuming process of invoking it.

Amendments offered pursuant to such agreements, however, are seldom successful. In the 109th and 110th Congresses, amendments considered in this manner failed 100 percent and 78 percent of the time, respectively. In the 111th and 112th Congresses, the percentages of amendments considered in this manner that failed were 61 percent and 87 percent, respectively. Most recently, 77 percent of the amendments considered pursuant to this tactic failed in the 113th Congress.

The use of unanimous consent agreements to set 60-vote thresholds on amendments can thus be interpreted as allowing the majority to facilitate the passage of legislation by allowing the minority to offer amendments without risking the adoption of a poison pill. This process does not present a problem for members of the majority party because they typically oppose the amendment in question, and a 60-vote threshold means that it is unlikely to pass. In addition, members of the majority are more likely to have their priorities included in the underlying bill before it reaches the Senate floor for consideration.

Minority party members, as well as those in the majority party who are out of step with their colleagues on the policy question at hand, often support this process begrudgingly because it provides an opportunity to offer an amendment and get a vote on it, all without having to expend the necessary resources to filibuster the underlying legislation. They may not get the opportunity to offer the amendment altogether if they reject the 60-vote threshold.

Setting 60-vote thresholds for amendments via unanimous consent agreements is central to the majority’s ability to control the agenda in the Senate today. Yet the tactic’s increased use in recent years is at odds with calls to reform, or eliminate, the legislative filibuster. This suggests that there is a growing constituency inside the Senate to increase the majority’s ability to control the legislative process while reducing the minority’s ability to leverage the filibuster to secure majority concessions. If this trend persists, the Senate risks becoming more majoritarian, and thus more dysfunctional, moving forward.

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