24/09/2026
This is an unbiased, apolitical post. Which one will prevail? Expanded power of judicial review or the sole power of the Senate to try and decide all cases of impeachment?
Under the 1987 Philippine Constitution, the Senate is explicitly granted the sole power to try and decide all cases of impeachment. Because impeachment is a sui generis proceeding—a unique hybrid of legal and political processes—the general rule is that the judiciary takes a hands-off approach to the Senate's internal rules and day-to-day trial mechanics. However, this "sole power" doesn't mean the impeachment court operates entirely unchecked. The Supreme Court retains its expanded power of judicial review, which obligates it to step in whenever there is a grave abuse of discretion amounting to a lack or excess of jurisdiction by any branch of government.
If the Senate were to enact a rule limiting the number of senators allowed to vote in an impeachment trial, this is exactly where that expanded judicial review would come into play. The Constitution specifically mandates that a conviction requires the concurrence of two-thirds of all the Members of the Senate. This isn't just a casual procedural guideline; it is a rigid constitutional formula that establishes the voting threshold based on the total, unrestricted membership of the chamber.
By creating an internal rule that sidelines certain senators from casting a vote, the Senate would be effectively rewriting an express constitutional limitation. The Supreme Court would not simply brush this off as a non-justiciable political question or a matter of internal house rule-making. Stripping duly elected senators of their constitutional duty to vote on an impeachment conviction constitutes a clear violation of the Constitution and a grave abuse of discretion. Consequently, this scenario falls squarely within the Court's expanded power of judicial review, allowing it to strike down the limiting rule and enforce the proper constitutional threshold.
