"Will Donald Trump be impeached?" is perhaps the question I get asked the most often these days. Sometimes the question starts with the word "when".
Speculation about Trump being impeached by Congress has run far ahead of careful analysis, insufficiently grounded in an understanding of the political realities underlying impeachment.
For instance, betting markets on the prospects of Trump's impeachment opened almost immediately after he became president. Centrebet's price on Trump being impeached in his first term fell from $2.50 to $2 and currently stands at $2.35, implying a 40 per cent chance that Trump will be impeached, fantastically high in my estimation.
It's political, not legal
Impeachment is not the same as removing the president. A majority vote of the House of Representatives is required to impeach a president. But impeachment is only a first step towards removal from office. After impeachment, a trial in the Senate and guilty votes from a super-majority of two-thirds of the Senate is needed to convict and remove a president from office.
Impeachment is political, an act of an elected legislature, albeit with legal overtones in form and procedure. Critically, criminal acts are neither necessary nor sufficient for impeachment and conviction of a president.
No US president has been convicted and removed from office. Just two presidents have been impeached by the House. Richard Nixon resigned before the House of Representatives voted on impeachment. Bill Clinton is just one of two presidents to be impeached and tried by the Senate; the other was Andrew Johnson (1868), whose trial in the Senate concluded with an acquittal, just one vote short of the two-thirds majority required for conviction. Resignation (Nixon) or death (four by natural causes; four by assassination) remain the only ways US presidents have left office prior to electoral defeat or term limits.
No President has ever been convicted by the Senate
Those three available historical cases support the following political logic of impeachment: A president who thought that two-thirds of the Senate would vote for conviction would resign prior to impeachment or trial, perhaps trading the timing and manner of their resignation for a pardon from their successor, protecting them against criminal prosecution, a la Nixon. Conversely, a president confident of the result of a trial in the Senate will not resign, a la Clinton. If so, then (a) we ought to never observe a successful conviction and removal of a president from office; (b) equivalently, Senate trials of presidents do not result in convictions. Both conclusions are consistent with the small number of historical cases.
Nixon, a Republican, faced impeachment and trial with Democratic majorities in both the House and Senate, but resigned when as it became clear that he had participated in the Watergate cover up and had engaged in a long campaign to conceal his knowledge of it. Conversely, Clinton was impeached with Republican majorities in the House of Representatives and Senate, but with near universal opposition to impeachment among Democratic House members. No Democratic Senator voted for Clinton's conviction in the Senate.
Public opinion remained firmly behind Clinton through 1998, as the Lewinsky scandal became public, Independent Counsel Kenneth Starr completed and published his salacious report on Clinton's wrongdoing, and the House impeached Clinton. Clinton went into his Senate trial with approval ratings in the high 60s.
Nixon lost support from everyone, Trump hasn't
In contrast, support for Nixon crumbled over 1973: aides resigned or were fired in an attempt to insulate the president, the Senate held sensational, televised hearings into the Watergate matter and Nixon unsuccessfully attempted to end the Watergate investigation. Nixon ended 1973 with the House Judiciary Committee conducting an impeachment investigation, his approval ratings in the 20s, where they would remain until his resignation in August 1974.
Clinton could thus stare down impeachment and trial in the Senate. Nixon could not.
Trump's aggregate approval numbers lie around the 40 per cent mark, low by historical standards for a president at this early stage. But his support among Republican partisans remains extremely high – 85 per cent, close to Democratic levels of support for Clinton through his impeachment and Senate trial, and a typical level of in-party support for a president at this stage of a presidential term. Nixon ended his presidency with a 50 per cent approval rating among fellow Republicans. Impeachment will remain out of the question so long as Republican partisans continue to support Trump the way they have thus far.
Special Counsel Robert Mueller – investigating ties between the Trump campaign and Russia and related matters – has less autonomy than did Kenneth Starr, the Independent Counsel investigating allegations against the Clintons and their associates. This suggests that Mueller's investigation may be completed more expeditiously than either the Watergate investigation (1973-74) or the series of investigations by Starr (1993-1998).
But … circumstances could change
Republican majorities in both House and Senate make it extremely unlikely that President Trump will be impeached or convicted in the current Congress. Even if an impeachment vote could get to the floor of the House of Representatives – and all 193 Democrats in the House voted for impeachment – at least 25 Republicans would have to vote for impeachment to obtain a 218-vote majority.
Then, if all 46 Senate Democrats and two Independent senators voted for conviction, at least 19 Republican senators would need to vote for conviction for Trump to be removed from office. This will not happen while Trump's approval rating remains at conventionally high levels among Republican partisans, given the intensely partisan nature of impeachment votes in the Nixon and Clinton cases.
Mueller's investigation continues and it would be rash to say that there is no set of circumstances that would see Republican legislators fail to support Trump. Mid-term elections in 2018 could also change the balance of power in the Congress, putting the votes for a Trump impeachment and conviction in closer reach.
But, for now, impeachment remains extremely unlikely.
Simon Jackman is the author of Impeachment 101: The history, process and prospect of a Trump impeachment.