Professor John Feerick was quoted in the Telegraph (UK) regarding the specific factors that constitute the 25th Amendment.
The amendment is vague about the specifics. However, John D Feerick, former dean of Fordham Law School who served as one of its architects, said Senators who signed the amendment into law were clear it must be based on “reliable facts regarding the president’s physical or mental faculties,” not personal prejudice.
“If you read the debates, it’s also clear that policy and political differences are not included, unpopularity is not included, poor judgment, incompetence, laziness, or impeachable conduct — none of that, you’ll find in the debates in the congressional record, is intended to be covered by Section IV,” he told Business Insider.