How does Congress initiate the process of removing a president under the 25th Amendment?

1. What triggers Congress’s role under Section 4

Congress is drawn into the 25th Amendment process only after the Vice President and a majority of the principal officers of the executive departments—or of “such other body as Congress may by law provide”—transmit a written declaration to the President pro tempore of the Senate and the Speaker of the House that the President is unable to discharge the office’s powers and duties; that transmission makes the Vice President immediately Acting President and starts the statutory clock for Congressional action ^{[1] [3]}.

2. The President’s immediate right to contest and the Cabinet’s four‑day backstop

If the President sends a written declaration to congressional leaders asserting no inability exists, the Vice President and the same majority of Cabinet officers have four days to counter with a second written declaration that the President remains unable to serve; that four‑day window is the immediate procedural hinge point that can escalate the matter to Congress if the Vice President and Cabinet persist ^{[1] [6]}.

3. Congress’s timeline and voting threshold

Once Congress receives the second declaration, it has twenty‑one days to decide the question, or, if not in session, twenty‑one days after it convenes; to keep the Vice President as Acting President permanently, both the House and the Senate must each reach a two‑thirds vote that the President is unable to discharge the duties of the office—otherwise the President resumes power ^{[1] [2] [6]}.

4. How this differs from impeachment and political implications

The 25th Amendment’s Section 4 is distinct from impeachment: impeachment and conviction remove a President for “high crimes and misdemeanors” and require a House vote to impeach and a two‑thirds Senate vote to convict, whereas the 25th Amendment’s congressional determination over capacity—by two‑thirds of both houses—addresses incapacity rather than criminal culpability, and therefore rests on different legal standards and evidentiary questions ^{[7] [8] [9]}.

5. Legal gray areas Congress must confront

Congress must decide not only whether a President is “unable” but what evidence suffices, who may testify or examine the President, and whether mental or behavioral conditions qualify—a set of unresolved legal and procedural questions that scholars, legislators, and courts have debated because Section 4’s language is vague and has never been judicially tested ^{[4] [6] [9]}.

6. Options for Congress to change the mechanics

Congress can reduce uncertainty by legislating the body that may join the Vice President (for example, creating a medical commission to assess capacity), by specifying procedures for hearings and testimony, and by clarifying evidentiary standards—proposals law professors and some members of Congress have advanced to make Section 4 less ad hoc and less vulnerable to political manipulation ^{[4] [10]}.

7. Political reality: high bar and high stakes

Practically speaking, the constitutional deadlines and the requirement of two‑thirds votes in both chambers make Congress’s role a high bar designed to prevent facile or partisan removals, but that same difficulty means using the 25th Amendment as a political check is rare and fraught with controversy about motive and legitimacy—an argument advanced by constitutional commentators and institutions warning against weaponizing Section 4 ^{[9] [3] [5]}.

8. Historical context and rarity of use

The 25th Amendment was ratified in 1967 to fill succession and disability gaps highlighted by presidential assassinations and illnesses, and while Sections 1 and 2 have been used for succession and vice‑presidential appointments, Section 4’s involuntary removal mechanism remains unused in U.S. history, leaving Congress to confront an untested constitutional remedy if ever called upon ^{[11] [5] [6]}.