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Who Has to Publish in the Federal Register?
The Comptroller General (GAO). If the GAO finds that an impoundment (rescission or deferral) violates the ICA, it must report it to Congress and publish it in the Federal Register.
This is a watchdog mechanism to ensure transparency after a violation has been found.
The President is only required to notify Congress. The law does not require the President's notification to be published in the Federal Register.
The Impoundment Control Act distinguishes between executive and legislative oversight roles.
The President's role is to request recissions or deferrals by formally notifying Congress.
The Congress's role (via the GAO) is to review whether the President is complying with the ICA and, if found to be in violation of the ICA - the GAO must then report THAT to Congress and publish in the Federal Register, 2 U.S.C. § 685(d).