Appropriations

The Constitution provides that no money shall be drawn from the Treasury but in consequence of appropriations made by law. An appropriation is legal authority to incur obligations and make payments for specified purposes, in specified amounts, during a specified period. It is distinct from an authorization, a law that creates or continues a program and may suggest a funding level, but does not itself provide any money. A program can be authorized and never funded, or funded without a current authorization.

Most discretionary spending is provided each year through the twelve regular appropriations bills, which together come to about 1.8 trillion dollars. Supplemental appropriations add money mid-year, usually for disasters or wars. Continuing resolutions extend funding temporarily when regular bills are late, and omnibus bills combine several or all regular bills. Mandatory spending, such as Social Security benefits and interest on the debt, is also legally appropriated, but through permanent appropriations in existing law that do not require annual votes.

The Antideficiency Act enforces the system. It forbids officials from spending more than Congress appropriated, spending before an appropriation is enacted, or accepting voluntary services, and violations can bring administrative discipline and, in theory, criminal penalties. That law is why agencies must shut down when appropriations lapse. Congress also attaches conditions and limits to appropriations, known as riders, which bar money from being used for particular purposes, making the annual bills a major vehicle for policy fights.