On Oct. 1, President Donald Trump and First Lady Melania Trump tested positive for COVID-19 [1]. The following day, after displaying what a White House physician called "mild symptoms" like a low-grade fever, Trump was admitted to the hospital at Walter Reed National Military Medical Center. As of now, Trump retains all of his powers as the President of the United States, despite his illness. But as he battles the disease, you might be wondering what could happen if at any point he becomes unable to serve.
Per the 25th Amendment [2], the standing president must inform the speaker of the House (Nancy Pelosi) and the president pro tempore (Chuck Grassley) in writing of their inability to serve; they must then inform them via another written statement when they are ready to serve again. In the interim, the vice president stands in for the president's duties. This has happened a few times in history: once when George H. W. Bush stood in for Ronald Reagan while he underwent colon cancer surgery under anesthesia in 1985, and twice when Richard B. Cheney stood in for George W. Bush while he underwent separate colonoscopies under sedation — once during his first term in 2002 and once during his second term in 2007.
If the president is incapable of declaring their incapacity, the vice president and a majority of Cabinet secretaries must then inform the speaker of the House and the president pro tempore of the president's inability to carry out their duties. At this point, the vice president steps in as acting president. While there is a protocol in place for this situation, the 25th Amendment also states that the vice president may declare the president unable to carry out their duties with the support of "such other body as Congress may by law provide [3]," which could include an independent review board, according to NPR. The qualifications for such a body are not spelled out clearly in the amendment and this means of transferring power has never been put into effect.
The Presidential Succession Act [4] sets up a line of succession to determine who takes over if the president is unable to serve due to illness, incapacitation, or death. The order has not always been agreed upon, and the law has a long history of changes, with the last taking place in 2006. That year, the USA Patriot Improvement and Reauthorization Act of 2005 [5] added the secretary of homeland security to the list.
In Trump's administration, here's the full line of succession:
Vice President Mike Pence
Speaker of the House Nancy Pelosi
Senate President Pro Tempore Chuck Grassley
Secretary of State Mike Pompeo
Secretary of the Treasury Steven Mnuchin
Secretary of Defense Mark T. Esper
Attorney General William Barr
Secretary of the Interior David Bernhardt
Secretary Bernhardt is pictured seated to the left of President Donald Trump [7].
Secretary of Agriculture Sonny Perdue
Secretary of Commerce Wilbur Ross
Secretary of Labor Eugene Scalia
Secretary of Health and Human Services Alex Azar
Secretary of Housing and Urban Development Ben Carson
Secretary of Transportation Elaine Chao
Secretary of Energy Dan Brouillette
Secretary of Education Betsy DeVos
Secretary of Veterans Affairs Robert Wilkie
Secretary of Homeland Security Chad Wolf
The only caveat here is that Secretary of Transportation Elaine Chao [8] isn't eligible since she was born in Taipei, Taiwan, and is therefore not a US-born citizen.
While it's still uncertain whether or not we'll need to refer to this list in the future, at least we know who we can expect if we do.
— Additional reporting by Ann-Marie Alcantara and Slade Warnken