The bill which is currently supported by 25 House Dems - including John Conyers as Ranking Member of the Judiciary Committee - proposes the creation of an "Oversight Commission on Presidential Capacity" which would hold the same kind of authority as the U.S. Cabinet to declare that the president is unable to discharge the powers and duties of his office.
This proposal is based on the following line from Section 4 of the 25th amendment:
"Whenever the Vice President and a majority of either the principal officers of the executive departments
or of such other body as Congress may by law provide, transmit to the President pro tempore of the Senate and the Speaker of the House of Representatives their written declaration that the President is unable to discharge the powers and duties of his office, the Vice President shall immediately assume the powers and duties of the office as Acting President."
https://www.yahoo.com/news/bill-create-panel-remove-trump-office-quietly-picks-democratic-support-124521145.html
