Antideficiency Act

The Antideficiency Act is a US federal law originally enacted in 1870 and substantially reformed in 1982, codified at 31 U.S.C. §§ 1341–1342. It prohibits federal agencies from spending or obligating funds in excess of amounts appropriated by Congress, making unauthorised expenditure a criminal offence for federal officers. The law is a cornerstone of congressional power over the public purse.

Its profile has risen sharply during the Iran conflict, where the White House has declined to request supplemental funding from Congress while drawing on existing Pentagon authorities to sustain operations. Legal scholars argue this arrangement, untested at current expenditure rates, may constitute spending beyond appropriated amounts in violation of the Act . Congress had already rejected a formal war authorisation request, compounding the legal exposure.

The Act sits at the intersection of two unresolved constitutional tensions: the president’s commander-in-chief authority and Congress’s exclusive power to appropriate funds. Enforcement depends entirely on political will; the Act has rarely been used to stop wartime spending already in motion, raising the question of whether it is a genuine constraint or a dormant formality.