Congressional Power of the Purse

Congressional power of the purse is the authority of the United States Congress to control federal spending, including money for military operations. Congress can use appropriations, laws that make funds available for specified purposes, to restrict the resources available to the President even though the President commands the armed forces.

Constitutional division of war powers

The Constitution divides military authority between Congress and the President, giving each a distinct role rather than placing all war powers in one branch.

• Article I, Section 9 provides that money may be drawn from the Treasury only pursuant to appropriations made by law.
• Article I, Section 8 empowers Congress to declare war, raise and support armies, and provide and maintain a navy; appropriations for supporting armies cannot exceed two years.
• Article II, Section 2 makes the President Commander in Chief, responsible for directing military operations within the constitutional framework.

How funding restrictions constrain operations

Congress can translate opposition to an operation into binding spending restrictions, rather than relying only on hearings or resolutions expressing disapproval.

• Congress can refuse new appropriations or decline to renew funding, limiting the resources available once existing lawful funds are exhausted.
• Congress can enact funding prohibitions that bar the use of covered funds for specified operations, deployments or geographical areas.
• Congress can impose spending ceilings, deadlines or conditions, including reporting or certification requirements before funds become available.
• Congress can preserve funds for withdrawal or troop protection while restricting funds for continuing or expanding combat.

Legal and practical limits

Authorization and appropriation serve different purposes: one supplies legal permission, while the other supplies spending authority. A restriction's effectiveness therefore depends on its precise wording and coverage.

• Under the War Powers Resolution, 1973, authority to introduce forces into hostilities is not inferred from an appropriation unless it specifically authorizes that introduction and states the required intent.
• Funding restrictions generally require passage by both Houses and presidential approval, or a veto override by two-thirds of each House.
• A narrowly drafted restriction may leave other legally available funding untouched; comprehensive restrictions must address relevant alternative funding sources and transfer authorities.
• The boundary between Congress's spending power and presidential command authority remains constitutionally contested, especially where restrictions resemble detailed battlefield direction.