Only two presidents in history have been impeached, but murmurs continue to surround Trump. Here’s how the process would work – if it would at all

On 21 July 2007, George W Bush underwent surgery to have five polyps removed after what was described as a routine colonoscopy. The date may have been lost to history, but for the rare invocation at the time of a constitutional amendment laying out how the transfer of power to the vice-president works in cases of presidential disability.

For 125 minutes – as long as it took for Bush to enter and emerge from partial anesthesia, eat breakfast and display possession of his native wit – Dick Cheney held all the powers attached to the office of the presidency. (Some wags have suggested that Cheney wielded that authority, unofficially, over a much longer time span.)

Even before the FBI director announced on Monday that the bureau is investigating possible collusion between the Donald Trump campaign and Moscow during the 2016 presidential election, the precise rules for how the powers of the presidency might be transferred – or simply rescinded – in case of criminality or emergency had become the subject of newfound and intense focus in the United States.

Another, more beautiful America is rising. Trump will be resisted | Rebecca Solnit Read more

Whispers about impeachment, the most familiar constitutional procedure for removing a president, began to circulate even before Trump had taken the oath of office. But two months into Trump’s presidency, those whispers – and the search for any other possible emergency exit – have grown into an open conversation that has moved well beyond the realm of a Democratic party daydream. “Get ready for impeachment,” an influential, 13-term Democratic congresswoman tweeted after the bombshell FBI announcement.

The Trump-Russia intrigue has produced a flood of speculation as to whether a new Watergate scandal was afoot. That crisis, which began with a break-in at Democratic party offices inside the Watergate hotel in 1972, brought down President Richard Nixon after two years, in the only resignation of an American president yet.

In a remarkable 77-minute press conference/performance artwork in February, Trump denied inappropriate ties to Moscow, which US intelligence agencies have concluded tampered with the presidential election in Trump’s favor. “I have nothing to do with Russia,” Trump said. “I told you, I have no deals there, I have no anything.”

But the significance of the allegations, and of the FBI investigation, is plain.

“On a 10 scale of Armageddon for our form of government, I would put Watergate at a 9,” wrote Dan Rather, the longtime network news anchor, in a Facebook post. “This Russia scandal is currently somewhere around a 5 or 6, in my opinion, but it is cascading in intensity seemingly by the hour. We may look back and see, in the end, that it is at least as big as Watergate. It may become the measure by which all future scandals are judged. It has all the necessary ingredients, and that is chilling.”

There are other grounds on which Trump might be removed from the presidency. A movement to impeach Trump for allegedly violating constitutional bans on receiving certain gifts – a problem rooted in the president’s failure to divest from his real estate, hotel and branding businesses – gained 875,000 online signatures in one month, said organizer John Bonifaz.

“I think there are many members of Congress who are deeply troubled,” said Bonifaz, a constitutional law expert and MacArthur fellowship recipient. “I think it’s only a matter of time before a resolution gets introduced in the United States Congress that starts this process of an impeachment investigation in the House of Representatives.”

In yet another scenario, as laid out in the 25th amendment to the constitution, which Bush invoked when he handed off power to Cheney, the vice-president, acting in concert with a majority of the cabinet, might declare the president unfit to serve. This is the most delicious scenario, for connoisseurs of political intrigue, though the amendment has never been invoked to remove power from a president against his will.

So what does the history of impeachment of US presidents tell us about where we might go from here?

Who has been impeached before?

Two presidents, Bill Clinton (1998) and Andrew Johnson (1868). (Congress may also impeach judges.) Articles of impeachment were passed against Richard Nixon by a congressional committee, but Nixon resigned before the House of Representatives could vote on the matter, meaning that technically he was not impeached.

Impeachment does not mean expulsion from office. Under the constitution, impeachment happens in the House of Representatives if a majority approves articles of impeachment previously approved in committee. Then impeachment goes to the Senate, where a two-thirds majority vote is required to convict the president, upon which he would be removed from office.

Both Johnson and Clinton were impeached in the House but then acquitted in the Senate and remained in office.

What can a president be impeached for?

“Treason, bribery, or other high crimes and misdemeanors”, the constitution says. Needless to say, there’s debate over what all those terms mean.

Johnson was charged with breaking the law by removing the US secretary of war, which, in the aftermath of the civil war, was not his decision as president to make. Clinton was charged with obstruction of justice and with perjury, for allegedly lying under oath to a federal grand jury about his affair with Monica Lewinsky.

Had Nixon not resigned, he might have been convicted in the Senate on one of three charges: obstruction of justice, abuse of power or defiance of subpoenas. In any case, President Gerald Ford, who was Nixon’s vice-president and who succeeded him, pardoned Nixon of any crimes a month after Nixon resigned.

Can a president be removed apart from through impeachment?

Theoretically, yes, under the aforementioned 25th amendment, which was ratified relatively recently, in 1967, to clear up succession issues made painfully urgent by the assassination of John F Kennedy.

The 25th amendment describes a process by which a president may give away power owing to his or her own disability (the Bush polyps case), and a separate process by which power may be taken from a president owing to disability or inability.

The key players in the second case are the vice-president and the top 15 members of the cabinet. If the former and a majority of the latter decide the president is “unable to discharge the powers and duties of his office”, they submit that information in writing to the House speaker (currently Paul Ryan) and Senate president pro tempore (currently the Utah Republican senator Orrin Hatch) and just like that, the vice-president would be acting president.

The president may challenge such a decision, at which point a two-thirds majority in both chambers of Congress would be required to stop the president from regaining power.

It’s conceivable that Trump would not go quietly if his cabinet and Vice-President Mike Pence were to gang up on him.

Facebook Twitter Pinterest Mike Pence: the man Republicans really want in charge? Photograph: Eric Vidal/Reuters

How long do impeachment proceedings take?

There isn’t much precedent to say, but the Clinton case proceeded through Congress relatively quickly, in about three months. That example may be misleading, however, owing to the years-long investigation of Bill and Hillary Clinton, including the Lewinsky affair, by the special prosecutor Kenneth Starr, which preceded it. Starr handed his report and research to the House judiciary committee, which therefore had no need to conduct a time-consuming investigation of its own.

Who’s saying Trump should be impeached?

About 46% of Americans who responded to a Public Policy Polling survey last month, for starters. Public opinion matters because for impeachment to happen, Congress must act, and elected officials sometimes hang their principles on opinion polls.

It’s notable that Nixon, a Republican, faced impeachment in a Congress controlled by Democrats, and Clinton was impeached by a Republican-controlled Congress. For Trump to be impeached, members of his own party would have to turn on him.

That’s why Republican base approval of Trump is so important. If Republican voters do not abandon the president, Republican members of Congress are not likely to.

On the other hand, the Republican Congress might conceivably be enticed into action by the prospect of dumping Trump in exchange for someone they are far more comfortable with: Pence, himself a former congressman and a much more predictable traditional conservative.

At least three congressional Democrats have called for impeachment proceedings of some kind. Representative Mark Pocan of Wisconsin said on the House floor in February that if Trump did not divest business holdings and take other actions, then “we’ll have to take other actions, including legislative directives, resolutions of disapproval and even explore the power of impeachment”.

What might Trump be charged with?

Bonifaz, of the Impeach Trump Now group behind the petition, argues that Trump’s failure to divest from his businesses has already produced frequent violations of constitutional rules for emoluments, or gifts. Investigations into associations with Russia by Trump or his proxies could conceivably produce some kind of disloyalty charge. If Trump has to testify at some point about any of this, he could face a Clinton-style perjury charge. Abuse of power? Obstruction of justice? It seems as if, should Congress get to the point of charging Trump, they may have a buffet of potential charges to choose from.

What would it take in practice to trigger enough Republicans into action?

Remember that Republicans had promised to impeach Hillary Clinton as soon as she took office. But what they might not have remembered is that two-thirds of the Senate is required to convict a president of impeachable offenses. The Democrats are in the minority, but they do have 48 Senate seats out of 100.

The most important factor for Republicans in deciding whether to go after Trump would seem to be the disposition of Republican voters. If the people turn on the president, Congress may follow.

Might Trump resign before he’s impeached if there’s a smoking gun, as Nixon did?

What kind of mood does Pence seem to be in? Is he implicated? In the scenario of a Pence succession, it would be up to the current vice-president to pardon Trump or not. Maybe Trump would be more likely to get out of the way and avoid all or some impeachment proceedings – in this truly hypothetical scenario – if Trump felt reassured that Pence, upon acceding to power, would pardon him.

Could he refuse to comply with proceedings?

Only two months into the Trump presidency, we’ve already heard warnings, issued by members of Congress, about this or that constitutional crisis being afoot: Trump impugns judges; Trump overrides legislated regulations; courts block executive actions. There are many opportunities for further constitutional crises during the Trump years, and a Trump refusal to go along with prospective impeachment proceedings is certainly easy to imagine. In which case: who controls the military?

Could he refuse to step down if he’s found guilty?

See above.

Would Pence go down with him?

Not likely. There’s a school of thought that says a key reason the Republican congressional majority would assent to a Trump impeachment is because then they would get the president they really want, Pence. The closest historical precedent to a double whammy of this kind is the resignation in a bribery scandal of Nixon’s vice-president, Spiro Agnew, in 1973, a year before Nixon went down. But the alleged crimes were unrelated.

Elections have consequences. Is this all actually just a fantasy for liberals and conservative purists who cannot accept that Trump won?

Understanding Trump’s narcissism could be the key to opposing him | Kamran Ahmed Read more

Reasons this might not be true include the fact of Trump’s historically low popularity rating at the two-month mark. Trump sits at 37% approval, according to Gallup, a whopping 24 points behind the historical average for first-term presidents. Additionally, Trump seems to be flying unusually close to the sun, in terms of his conduct as an elected official. During his campaign he refused to release his tax returns on the grounds that the usual rules did not apply to him. His refusal to divest from his businesses as president, on similar grounds, could lead him into legal hazards that other presidents have avoided. Finally, Trump is truly a Washington outsider, which could increase his vulnerability to acts of bureaucratic infighting or hidden treachery, as evidenced by the incredible number of leaks from the intelligence community so far.

On the other hand, the election of Trump has been a particularly painful blow to the progressive psyche, more so even perhaps than the re-election of Bush as the atrocities of the Iraq war mounted in 2004. Republicans suffered for eight years from what some of their critics called Obama derangement syndrome, becoming so wrapped up in their opposition to the president that any sense of greater purpose seemed sometimes to be lost. Are progressives and conservative purists suffering from Trump derangement syndrome? It’s possible. We’ll find out.