There are reasons why no sitting president has ever been removed from office after being impeached. The process needs broad agreement within Congress and requires some members to vote against their party’s interests. There are multiple steps. It begins with the House Judiciary Committee, which must put forward a case for why the president has committed «treason, bribery, or other high crimes and misdemeanours». This wording is deliberately vague to account for the many potential transgressions of a president. If the House votes by a simple majority on any article, the case is then passed to the Senate (the upper house) for trial. The chief justice presides and a select group of House members act as prosecutors. The 100 members of the Senate comprise the jury. Two-thirds of senators need to support a guilty verdict to remove the president from office. In the short history of attempted impeachments, Richard Nixon resigned in 1974 before a vote could be held in the House, and the Senate acquitted both Andrew Johnson in 1868 and Bill Clinton in 1999.

Three and a half more years

Our central forecast remains that Mr Trump will see out his presidential term. This is for three reasons. First, Mr Trump will continue to be useful to the Republican Party. Congressional Republicans are focused on advancing their policy agenda, especially on tax reform and healthcare. Given that the party has majorities in both chambers of Congress, 2017‑18 represents a huge opportunity to make major changes. Mr Trump will be acquiescent on these issues, and therefore keeping him in the presidency would benefit Republicans. Launching an impeachment process would divert attention away from the Republican agenda and, we believe, damage the party’s prospects at the 2020 elections. Impeachment would reflect badly on the party, as well as on the president.

Second, Congress is highly polarised. There are various measures to assess the ideological positions of Democrats and Republicans, but according to the DW‑Nominate estimate, produced by two academics, Keith Poole and Howard Rosenthal, Democrats are drifting towards more liberal positions and Republicans, especially, towards more conservative ones. The two parties now sit further apart than at any point since the survey began in the 1870s. Polarisation matters because it means that the parties are less likely to co-operate on any given issue, including impeachment. In our view, this means that House Republicans are less likely to vote Mr Trump out. (It also means, we think, that Democrats are more likely to push for impeachment, but we do not believe that they will have this opportunity.)

This is because of our third reason: we expect Republicans to hold on to their House majority at the November 2018 mid-term elections. The party holds 238 seats, with 218 needed for control. This sounds like a relatively slim advantage, especially given that governing parties tend to lose seats at the mid-terms. But gerrymandering and redistricting mean that few House seats are genuine contests. According to the Cook Political Report, only 23 seats are considered «highly competitive». Political polarisation also makes it more likely that seats will not shift from one party to the other, as the ideological change required would be greater. Unless there is a major, broad-based swing against the Republican Party over the next 18 months, the Republicans will be in a strong position to keep the House.

Dark deeds

But even though we are maintaining our central forecast that Mr Trump will remain in office, there are several major risks to this view. Taken together, they justify a rise in the likelihood of impeachment from low to moderate. The first, and most serious, is that Robert Mueller, the special counsel appointed to investigate potential links between Mr Trump and Russia, uncovers evidence of wrongdoing sufficiently serious to turn Republican sentiment against Mr Trump. Were this to occur, senior Republicans, such as Paul Ryan and Mitch McConnell, would decide that the damage done to the Republican Party would be greater if it continued to support the president than if it decided to cut him loose.

At present, there is already some evidence of dubious behaviour on the part of Mr Trump, including his open admission that Mr Comey’s investigation into Russia prompted the president to fire him. Other building-blocks towards a case of «high crimes and misdemeanours» might include Mr Comey’s account of being put under pressure by Mr Trump to drop his investigation into Michael Flynn; Mr Trump’s failure to separate himself from his business empire; and his careless handling of classified information. So far, none of these behaviours has shifted Republican sentiment, but it is possible that Mr Mueller may uncover something that makes defending Mr Trump impossible.

Next, the Republicans might lose the House (and even the Senate, but this is highly unlikely) in 2018. So far, the government’s progress on its policy agenda has been lethargic. Healthcare remains a mess, with the House passing the buck to the Senate to sort this out. Tax reform amounts to a single-pager, with no costings or thresholds, nor any consensus on how a huge tax cut would be financed. The government has watered down rather than intensified its rhetoric on «unfair» international trade agreements. It is possible that legislative lethargy, combined with the chaos emanating from the White House, might prompt voters to shift allegiance at the mid-term elections and hand control of the lower house to the Democrats. This would vastly increase the chances of an impeachment vote in the chamber. (The likelihood of the Senate approving the impeachment would remain subject to a much broader range of factors.)

Other levers to pull

Another risk to the completion of the Trump presidency comes from the 25th amendment, which permits the removal of a president from office if he is judged to be unable to discharge the powers and duties of his office. For the amendment to be invoked, the vice-president and a majority of the cabinet must agree and receive backing from two-thirds of Congress. The amendment was designed to protect the presidency if its occupant were subject to an assassination attempt or succumbed to a debilitating illness. It is doubtful that its authors imagined it to be used to remove a president on grounds of incompetence. We consider the likelihood of the amendment being used to remove Mr Trump as extremely low. The lack of precedent is important, as is the required collaboration of several of his closest allies and Congress. Given the latitude already allotted to Mr Trump and his behaviour, it is hard to imagine what he would have to do to cause the 25th amendment to be invoked ahead of impeachment proceedings.

There is also some, unquantifiable, risk of Mr Trump resigning. Despite the best efforts of the media to scrutinise his body language and his tweets, it is all but impossible to discern the president’s morale. He has told Reuters that he thought the presidency would be easier than it had proved to be and that he missed his former life. It would be unwise to extrapolate too much from a single quote, but it is not too big a leap to imagine that consistent record-low approval ratings, bickering among his closest advisers, daily press intrusion, a hectic schedule and the pressure on family life might make the 70‑year-old president think twice about the years until 2020. More than anything, Mr Trump likes to win. Resignation, almost by definition, would be a defeat. So Mr Trump would either need to be backed into a corner—perhaps like Nixon, by the near-certainty of impeachment—or he would need a story that would somehow allow him to bow out on top. His flexible relationship with the truth might just allow him to create such a narrative, even if much of the American population and the media disagreed with him.

Following The Donald

Were Mr Trump to leave office early, either of his own volition or under the disgrace of impeachment, his term would be completed by his vice-president, Mike Pence. (If Mr Pence, too, were impeached, the presidency would go to Mr Ryan.) The appeal (or otherwise) of the vice-president to the Republican Party is another factor in determining the likelihood of impeachment. Mr Pence is a comforting figure for Republicans to have as first reserve: he offers the promise of advancing the Republican agenda on healthcare and taxes but without the drama and volatility that come with Mr Trump. He knows Washington well, having served in Congress since 2001. As a staunch social conservative, he would satisfy the Tea Party wing.

But the notion of a Pence presidency as a fresh start is faulty. Mr Pence has remained thoroughly loyal to Mr Trump and has refused to entertain questions about a potential presidential run in 2020. This has cultivated his reputation as a decent man and a safe pair of hands. It has also meant that he will be stained by the dysfunction of the Trump presidency. Just as Gerald Ford struggled to escape the shadow cast by succeeding Nixon, so Mr Pence would find it hard to govern as his own man. Like Mr Trump, Mr Pence would need to overcome divisions within the Republican Party. In all likelihood, he would run a more effective administration, but his ascendancy to the White House would embolden the Tea Party and make finding unity in the GOP more difficult.

For now, we believe that there are compelling reasons to expect Mr Trump to complete his term. Perhaps counter-intuitively, the appointment of Mr Mueller will cool the political temperature in Washington. Democrats will be calmer, knowing that a safe pair of hands is leading the Russia investigation. Mr Comey’s testimony to Congress is likely to reveal more unflattering details for Mr Trump, but they are unlikely to result in impeachment proceedings until the investigation is complete—and that could take a year or more. With fewer alarming headlines, the Republican Party is less likely to suffer a massive swing against it in the mid-term elections, ensuring that it keeps control of the House. Maintaining the party’s majority in the chamber will be Mr Trump’s best insurance to keep himself in office. As always, we note that the president’s impulsive character and disregard for protocol means that the unlikely is still possible. But it would take a significant shift in mood, even allowing for his existing transgressions, to switch Republican loyalty away from Mr Trump.

Will the Trump presidency survive?

The Economist    May 26, 2017