Pocket veto
A bill that fails because the president neither signs nor returns it while Congress is adjourned.
A president presented with a bill has ten days, excluding Sundays, to sign it or return it with objections. If the president does nothing and Congress is in session, the bill becomes law without a signature. If Congress has adjourned so that the bill cannot be returned, it simply dies. That second outcome is the pocket veto.
Its distinguishing feature is that it cannot be overridden. An ordinary veto returns the bill to Congress, which may override it by a two-thirds vote in both chambers. A pocket veto leaves nothing to override, so the measure is defeated absolutely, and the only remedy is to pass it again in a later session.
What counts as an adjournment preventing return has been disputed between the branches for decades, and Congress has used pro forma sessions specifically to keep the return route open. The practical points for a reader are the calendar and the arithmetic: bills presented near the end of a session are the vulnerable ones, and an override needs two-thirds, not the sixty votes that cloture requires.
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