There’s a new political controversy in the US – involving Donald Trump, foreign nationals, questions about legal and ethical behaviour, and allegations against a political rival – and it’s all led to an impeachment inquiry into the US president.
The story can be difficult to follow, so here are some answers to the most pressing questions.
Why is this important?
Mr Trump’s critics accuse him of using the powers of the presidency to bully Ukraine into digging up damaging information on a political rival, Democrat Joe Biden.
Mr Trump and his supporters allege the former vice-president abused his power to pressure Ukraine to back away from a criminal investigation that could implicate his son, Hunter.
Mr Biden is the front-runner for the Democratic nomination to take on Mr Trump next year.
In other words, it is nothing less than the White House at stake.
- Why Ukraine has become ensnared in US collusion claims
- Hunter Biden’s Ukrainian gas connection
Where does this row stem from?
Mr Trump and Ukrainian President Volodymyr Zelensky had a phone conversation on 25 July this year.
A rough transcript of the call shows that the US president pressed his Ukrainian counterpart to investigate former Vice-President Biden and his son, who was a board member for a company owned by a Ukrainian oligarch.
The call came after the Trump administration had delayed releasing US military funds to Ukraine until mid-September.
Mr Trump also referenced the 2016 hacking of the Democratic email server in the call to Mr Zelensky, and seemed to imply that the server still exists somewhere in Ukraine.
The US president says he has done nothing wrong, calling the impeachment proceedings a “joke”.
He has accused Democrats of themselves threatening Mr Zelensky by withholding their votes on US laws affecting Ukraine, and says the controversy was created in order to distract from Mr Trump’s meetings at the United Nations.
What are other US politicians saying?
Congressional Democrats say the phone call – raised by a whistleblower in a formal complaint – is proof Mr Trump brought improper pressure on a foreign power for personal gain.
Democrats say the president wanted the Ukrainians to start the investigation into corruption because this could sully the reputation of Hunter and his father.
Several Republicans came forward after the partial transcript of the call was released to defend Mr Trump. This shows the partisan nature of the controversy, which has – like much else in Washington – been divided by party politics.
However, at least one Republican, Mitt Romney, a US senator from Utah, said he would like to know more.
What was in the whistleblower’s complaint?
We still don’t know.
Initial reports painted the complaint as a troubling account of the president’s dealings with a foreign leader.
For days after details of the complaint emerged the Trump administration refused to share it but amid growing pressure it changed tack.
President Trump has now pledged transparency and the release of the phone transcript formed part of this – the president said it would show the call was “totally appropriate”.
The transcript released though was not a full, verbatim account, but rather notes of the conversation taken by US officials who listened in.
The complaint itself was released to the House and Senate Intelligence committees on Wednesday and reports suggest that negotiations are under way to allow the still unknown whistleblower to testify.
Joseph Maguire, the acting director of national intelligence, is scheduled to testify publicly before the House Intelligence Committee on Thursday.
Did the president do something illegal?
The most damning allegation is that the president pressured a foreign leader for damaging information about a political opponent while holding out the prospect of US military aid.
Is that illegal? We do have some very recent precedent.
It certainly recalls the recently concluded two-year Robert Mueller investigation into possible Trump campaign ties to Russian election-meddling in 2016.
The special counsel’s report detailed multiple contacts between the campaign and Russian nationals, including the June 2016 meeting between top campaign officials such as Donald Trump Jr and several Russians with ties to the Kremlin.
There has been some debate over whether soliciting opposition research from a foreign government constitutes a campaign finance violation, but Mr Mueller declined to file charges.
Mr Trump’s Ukrainian call could also potentially run afoul of federal bribery statutes. The special counsel concluded that Justice Department policy guidelines prohibit a sitting president from being indicted, however, so even if Mr Trump did commit some kind of crime with his actions, he’s safe at the moment from criminal prosecution.
With this in mind, a more relevant question might be …
Did Mr Trump commit an impeachable offence?
The constitutional process for handling a president who committed illegal and-or unethical acts is impeachment by a majority of the House of Representatives and conviction and removal by a two-thirds majority of the US Senate.
The US constitution outlines the grounds for impeachment as “treason, bribery, or other high crimes and misdemeanors”. When it comes down to it, an “impeachable offense” is whatever a majority of the House says it is.
- How easy is it to impeach a president?
- Is Donald Trump allowed to spill secrets?
Ever since the conclusion of the Mueller investigation, the drumbeat for impeachment among Democrats – who hold a comfortable majority in the House – has been steadily increasing. Initially, however, the House Democratic leadership was loath to push ahead with a formal investigation that could lead to an impeachment vote.
Speaker of the House Nancy Pelosi had suggested that such a move could damage the electoral prospects of Democrats in moderate congressional districts and would in the end be meaningless because the Republicans who hold the majority in the Senate would never vote to remove the president.
But then on Tuesday, Ms Pelosi announced that Democrats were opening a formal impeachment inquiry.
She said the president had committed “a violation of the law”, and called his actions “a breach of his constitutional responsibilities”. She said he “must be held accountable”.
Is there anything to these allegations about Joe Biden and his son?
The allegations against the Bidens pushed by Mr Trump and his lawyer, former New York City Mayor Rudy Giuliani, centre on the then-vice-president’s successful effort to force out top Ukrainian prosecutor Viktor Shokin in 2016.
Mr Shokin’s office was responsible for investigations into a Ukrainian gas company, Burisima Holdings, which at the time was paying Hunter Biden, Mr Biden’s son, as much as $50,000 a month to serve on its board of directors.
Mr Trump, Mr Giuliani and others allege that the vice-president’s pressure, which included the threat to withhold $1bn in US loan guarantees to the country, was an effort to protect his son and his company from potentially criminal exposure.
No evidence has so far been produced to indicate that Joe Biden either acted corruptly or was influenced by his son’s work in Ukraine.
However, critics believe at the very least the Biden family’s ties to Ukraine raise the perception of a possible conflict of interest.
Cutting against these allegations is the fact that Mr Biden was not the only public official – in the US, among EU countries and in Ukraine – calling for Mr Shokin’s removal.
And as the New York Times recently noted, the Ukrainian prosecutor was not “aggressively pursuing” investigations into Burisima at the time, but was accused of using the threat of prosecution to solicit bribes from company leaders.
In addition, Mr Shokin’s replacement, Yuriy Lutsenko, continued to investigate Burisima for 10 months before ending all legal proceedings.
Reporting by Anthony Zurcher and Tara McKelvey