Backdoor spending authority
Backdoor spending authority in the federal budget is budget authority to incur obligations that evades the normal Congressional appropriations process because it is provided in legislation other than appropriation acts.The most common forms are borrowing authority, contract authority, and entitlement authority. From the perspective of the appropriations committees, funding by these forms of spending authority slips away from their control through legislative back doors. However, the Congressional Budget Act of 1974 gave those committees some control over new borrowing and contract authority. 
- Glossary of Terms in the Federal Budget Process, Louise M. Slaughter.