Amendment Tree / Filling the Tree (

From the Congressional Glossary – Including Legislative and Budget Terms

Amendment Tree / Filling the Tree


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Amendment trees” are charts that illustrate certain principles of precedence that guide the Senate amendment process. When all of the amendments permitted simultaneously by these principles of precedence have been offered and are pending, an amendment tree is said to be “filled,” and no additional amendments may be offered until one or more of those pending is disposed of or laid aside. Given that the presiding officer traditionally affords the Senate majority leader or his designee priority over all others in being recognized, a majority leader can repeatedly secure recognition and “fill the amendment tree” by sequentially offering all of the amendments permitted under applicable circumstances. By doing so, a leader can “freeze” the amendment process in place, blocking additional floor amendments, at least temporarily.

Degrees of Amendment: Designations that indicate the relationship of an amendment to the text of a measure and of one amendment to another. Amendments are permitted only in two degrees.

An amendment to the base text is called a first-degree amendment. Such an amendment can be further amended by either a substitute amendment (which is also a first-degree amendment) or a perfecting amendment, called a second-degree amendment. The substitute is also subject to a perfecting amendment. These four amendments constitute what is referred to as the amendment tree. Once an amendment to a measure is pending, either a perfecting amendment or a substitute amendment can be offered first.

The option of resolving differences between the two houses, i.e., Amendments Between the Houses–the process of amendments between the houses–allows two degrees of amendments. The amendment of the second chamber is considered text that is subject to amendment. Each chamber has one opportunity to propose an amendment to the amendment of the other chamber. The process is often conducted by informal negotiations between the members and staff of the committees of jurisdiction in the two houses. An extended exchange of amendments is rare.

Section 6.122 House Amendment Tree, from the Congressional Deskbook, Copyright 2012 by TheCapitol.Net, All Rights Reserved

Section 6.122 House Amendment Tree, from the Congressional Deskbook, Copyright 2012 by TheCapitol.Net, All Rights Reserved

A majority leader might “fill the tree” in this way to prevent the offering of or voting on of non-germane amendments, to try to speed up consideration of a measure, or to control the subject or sequence of amendments that may be offered.

If all four of these amendments are pending, the order of voting is as follows:
 1. the perfecting amendment to the amendment to the bill (a second-degree amendment)
 2. the perfecting amendment to the substitute (a second-degree amendment)
 3. the substitute (considered a first-degree amendment)
 4. the base amendment to the text
When an amendment has been disposed of, a branch of the amendment tree is open. An additional amendment may then be offered, provided that the new amendment does not propose to change what has already been amended.


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Legislative Drafter's Deskbook: A Practical Guide

Legislative Drafter’s Deskbook: A Practical Guide

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Citizen's Handbook to Influencing Elected Officials

Citizen’s Handbook to Influencing Elected Officials: Citizen Advocacy in State Legislatures and Congress: A Guide for Citizen Lobbyists and Grassroots Advocates

Congressional Directory

Congressional Directory, from TheCapitol.Net


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