The Byrd Rule is a Senate rule that amends the Congressional Budget Act of 1974 to allow Senators, during the Reconciliation Process, to block a piece of legislation if it purports significantly to increase the federal deficit beyond a ten-year term or is otherwise an "extraneous matter" as set forth in the Budget Act. It is named after West Virginia Senator Robert Byrd

Robert Byrd

Robert Carlyle Byrd was a United States Senator from West Virginia. A member of the Democratic Party, Byrd served as a U.S. Representative from 1953 until 1959 and as a U.S. Senator from 1959 to 2010...

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Reconciliation generally involves legislation that changes the budget deficit (or conceivably, the surplus). The "Byrd Rule" ' onMouseout='HidePop("89282")' href="/topics/Robert_Byrd">Robert Byrd

Robert Byrd

Robert Carlyle Byrd was a United States Senator from West Virginia. A member of the Democratic Party, Byrd served as a U.S. Representative from 1953 until 1959 and as a U.S. Senator from 1959 to 2010...

) was adopted in 1985 and amended in 1990 to outline which provisions reconciliation can and cannot be used for. The Byrd Rule defines a provision to be "extraneous" (and therefore ineligible for reconciliation) in six cases:

1. if it does not produce a change in outlays or revenues;
2. if it produces an outlay increase or revenue decrease when the instructed committee is not in compliance with its instructions;
3. if it is outside the jurisdiction of the committee that submitted the title or provision for inclusion in the reconciliation measure;
4. if it produces a change in outlays or revenues which is merely incidental to the non-budgetary components of the provision;
5. if it would increase the deficit for a fiscal year beyond those covered by the reconciliation measure, though the provisions in question may receive an exception if they in total in a Title of the measure net to a reduction in the deficit; and
6. if it recommends changes in Social Security
   Social Security (United States)
   In the United States, Social Security refers to the federal Old-Age, Survivors, and Disability Insurance program.The original Social Security Act and the current version of the Act, as amended encompass several social welfare and social insurance programs...
   
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Any senator may raise a procedural objection to a provision believed to be extraneous, which will then be ruled on by the Presiding Officer

Presiding Officer of the United States Senate

The Presiding Officer is the person who presides over the United States Senate and is charged with maintaining order and decorum, recognizing members to speak, and interpreting the Senate's rules, practices and precedents...

, customarily on the advice of the Senate Parliamentarian

Parliamentarian of the United States Senate

The Parliamentarian of the United States Senate is the official advisor to the United States Senate on the interpretation of Standing Rules of the United States Senate and parliamentary procedure....

. A vote of 60 senators is required to overturn the ruling. The Presiding Officer need not necessarily follow the advice of the Parliamentarian, and the Parliamentarian can be replaced by the Senate Majority Leader

Party leaders of the United States Senate

The Senate Majority and Minority Leaders are two United States Senators who are elected by the party conferences that hold the majority and the minority respectively. These leaders serve as the chief Senate spokespeople for their parties and manage and schedule the legislative and executive...

.. However, this has not been done since 1975.