When is prohibition a remedy?

According to Section 2 of Rule 65 of the Rules of Court, a petition for prohibition may be availed of under the following circumstances:

Sec. 2. Petition for prohibition. -

When the proceedings of any tribunal, corporation, board, officer or person, whether exercising judicial, quasi-judicial or ministerial functions, are without or in excess of its or his jurisdiction, or with grave abuse of discretion amounting to lack or excess of jurisdiction, and there is no appeal or any other plain, speedy, and adequate remedy in the ordinary course of law, a person aggrieved thereby may file a verified petition in the proper court, alleging the facts with certainty and praying that judgment be rendered commanding the respondent to desist from further proceedings in the action or matter specified therein, or otherwise granting such incidental reliefs as law and justice may require.

Prohibition is a legal remedy, provided by the common law, extraordinary in the sense that it is ordinarily available only when the usual and ordinary proceedings at law or in equity are inadequate to afford redress, prerogative in character to the extent that it is not always demandable of right, to prevent courts, or other tribunals, officers, or persons, from usurping or exercising a jurisdiction with which they have not been vested by law.[1]

The writ of prohibition, as the name imports, is one which commands the person to whom it is directed not to do something which, by suggestion of the relator, the court is informed he is about to do. If the thing be already done, it is manifest the writ of prohibition cannot undo it, for that would require an affirmative act; and the only effect of a writ of prohibition is to suspend all action and to prevent any further proceeding in the prohibited direction.[2] Prohibition, as a rule, does not lie to restrain an act that is already a fait accompli.[3]

[1] Feria, "Civil Procedure Annotated," Vol. II (2001 ed.), pp. 475-476.

[2] CabaƱero and Mangornong v. Torres, 61 Phil. 522, 525 (1935).

[3] Aguinaldo v. Commission on Elections, 368 Phil. 253, 263 (1999).