WASHINGTON — President Trump is under intense scrutiny over a classified whistle-blower complaint about his behavior, which at least partly involves his dealings with Ukraine’s new president and Mr. Trump’s call for Ukraine’s government to investigate former Vice President Joseph R. Biden Jr., who is a leading candidate for the 2020 Democratic presidential nomination.
Here are some of the basic facts behind the controversy.
What did Mr. Trump do?
In a July 25 phone call with the president of Ukraine, Volodymyr Zelensky, Mr. Trump pressed Mr. Zelensky to investigate Mr. Biden’s younger son, Hunter, who sat on the board of a Ukrainian energy company. Mr. Trump has seized on an unsubstantiated theory that when Mr. Biden, as vice president in 2016, conditioned a $1 billion loan guarantee on the firing of Ukraine’s top prosecutor, he was trying to protect the company from prosecution. Rudolph W. Giuliani, one of Mr. Trump’s personal lawyers, has pushed the Ukrainian government to investigate the matter and to explore whether there was impropriety involved in its decision in 2016 to release incriminating information about Mr. Trump’s campaign chairman at the time, Paul Manafort.
Why is this coming up now?
Because of an intelligence community whistle-blower who filed a complaint last month about the president’s actions. An inspector general deemed the complaint “credible” and “urgent” and forwarded it to the acting director of national intelligence, Joseph Maguire, who has refused to share it with Congress. The issue was brought out into the open when the House Intelligence Committee chairman, Representative Adam B. Schiff, Democrat of California, sent an angry letter to Mr. Maguire on Sept. 10 demanding the complaint be shared with his panel. Reporting since then by The New York Times and other news outlets has filled in some of the substance.
What did the whistle-blower claim?
The full extent of the whistle-blower’s complaint, as well as the whistle-blower’s identity, is not publicly known because Mr. Maguire will not share it. (He says that is because the complaint entails matters potentially covered by legal “privilege” and concerns conduct by someone outside the intelligence community.) Reporting by The Times and others has established that the complaint involves Mr. Trump’s interactions with Ukraine and a phone call with a foreign leader — possibly, but not necessarily, Mr. Zelensky. It is not clear if it includes other matters.
Did Mr. Trump use American foreign policy to pressure Ukraine to investigate a political rival?
This is the big question. The White House this summer blocked a package of military assistance to Ukraine. The aid was intended to help the country defend itself from Russian territorial aggression, including a military conflict in eastern Ukraine that has killed more than 13,000 people since 2014. The aid was first publicly disclosed as delayed about a month after the July phone call between Mr. Trump and Mr. Zelensky. Mr. Trump is not known to have openly linked the aid — which has since been released — to his demands for political investigations, but many Democrats believe that may be the case. This month, three Democratic House committee chairmen sent letters to the State Department and the White House warning that it would be “a staggering abuse of power, a boon to Moscow and a betrayal of the public trust” if Mr. Trump was withholding the military assistance to “improperly pressure the Ukrainian government to assist the president’s bid for re-election.”
What does Mr. Trump say?
The president insists that he has been unfairly accused, saying — without offering evidence — that the whistle-blower is “partisan” and that Democrats and the news media are initiating a new “witch hunt” against him. Mr. Trump has said that he is aware that his conversations with foreign leaders are monitored by numerous government officials and that he would not incriminate himself so easily. More specifically, Mr. Trump told reporters on Friday that his July call with Mr. Zelensky “was a totally appropriate conversation — it was actually a beautiful conversation.” Mr. Trump also repeated his unsubstantiated assertion that Mr. Biden improperly pressured the Ukrainian government.
What is Mr. Giuliani’s role in this?
As Mr. Trump’s personal lawyer, Mr. Giuliani has communicated with Ukrainian officials for months about the Bidens, as well as about the circumstances of the 2016 disclosures of payments earmarked by a Russia-aligned Ukrainian political party to Mr. Manafort, who is now serving a prison sentence on charges related to his Ukrainian political work. Mr. Giuliani has sought information about both matters, and traveled to Madrid this summer for a meeting with one of Mr. Zelensky’s top aides, whom he urged to investigate the matters.
Did Mr. Biden do something wrong?
There is no evidence that Mr. Biden intentionally tried to help his son when he pushed for the dismissal of the Ukrainian prosecutor, who was widely seen in the West as corrupt. Stamping out high-level corruption in Ukraine has long been a central goal of United States policy toward the country, and a standard condition for Western aid. Mr. Biden played a lead role in the Obama administration’s diplomacy with Kiev, but Obama administration officials worried that his son’s work for the energy company, Burisma Holdings, could create at least the perception of a conflict of interest. The United States and other Western governments had previously pressed Ukraine to pursue corruption investigations into Burisma and Mykola Zlochevsky, the oligarch who owned it. Those investigations did not yield convictions, which American officials said was at least partly because the Ukrainian prosecutors were intentionally stymieing the efforts. Mr. Zlochevsky’s allies, on the other hand, contended that the corruption claims were baseless and that the threat of prosecution was merely being used to try to solicit bribes from him or his allies.