Flustered Nancy Pelosi: “We’re Going to Be Talking About the 25th Amendment.”

Section 4 is the most controversial part of the 25th Amendment: It allows the Vice President and either the Cabinet, or a body approved “by law” formed by Congress, to jointly agree that “the President is unable to discharge the powers and duties of his office.” This clause was designed to deal with a situation where an incapacitated President couldn’t tell Congress that the Vice President needed to act as President.

It also allows the President to protest such a decision, and for two-thirds of Congress to decide in the end if the President is unable to serve due to a condition perceived by the Vice President, and either the Cabinet or a body approved by Congress. So the Cabinet, on its own, can’t block a President from using his or her powers if the President objects in writing. Congress would settle that dispute and the Vice President is the key actor in the process.
The potential use of Section 4 to remove a President from office as part of a political dispute is very controversial. And some constitutional observers feel that isn’t the intent behind the 25th Amendment.