Prior to the impeachment and eventual acquittal of President Donald Trump, a bill calling for a presidential oversight commission to evaluate Trump -- and possibly deem him unfit for office -- had initially gained the support of multiple Democrats.

In April 2017, Rep. Jamie Raskin, D-Md., introduced a bill in April for the Oversight Commission on Presidential Capacity Act. As part of the bill, an 11-member commission would include doctors and determine if the president "is mentally or physically unable to discharge the powers and duties of the office."

The bill says that the commission would "carry out section 4 of the 25th Amendment." Fox News breaks down what the constitutional amendment entails.

What is the 25th Amendment?

The amendment is made up of four sections, and lays out how the president would be succeeded in office.

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Why do we have the 25th Amendment?

The Constitution had been unclear about presidential succession before the amendment was ratified, according to the Gerald R. Ford Presidential Library and Museum. The amendment was debated following President John F. Kennedy's 1963 assassination, which left President Lyndon B. Johnson without a vice president, the U.S. Senate website explains. The amendment was ratified in 1967.

What does the first section of the amendment say?

It says that if the president is removed from office, resigns, or dies, the vice president becomes president.

What about the 25th Amendment's second section?

The president will nominate someone "who shall take office upon confirmation by a majority vote of both Houses of Congress" if there isn't a vice president.

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What does the amendment's third section say?

The vice president will serve as acting president, if the president tells the President pro tempore and the Speaker of the House of Representatives that he cannot "discharge the powers and duties of his office." The vice president would continue in the role unless the president says that he can serve.

What about the fourth section?

The vice president would serve as acting president if he "and a majority of either the principal officers of the executive departments or of such other body as Congress may by law provide" tell the President pro tempore of the Senate and the Speaker of the House that the president is unable to do his job. The amendment says that Congress would convene if there was a dispute over the president's ability to serve.