The rundown on Trump, Biden and a whistleblower's complaint

President Donald Trump is under intense scrutiny over a classified whistleblower complaint about his behaviour, which at least partly involves his dealings with Ukraine's new president and Trump's call for Ukraine's government to investigate former Vice President Joe Biden, who is a leading candidate for the 2020 Democratic presidential nomination.

Here are some of the basic facts behind the controversy.

What did Trump do?

In a July 25 phone call, Trump is said to have pressed the president of Ukraine, Volodymyr Zelenskiy, to investigate Biden's younger son, Hunter, who sat on the board of a Ukrainian energy company. Trump has seized on an unsubstantiated theory that Biden was trying to protect the company from prosecution when he called for the firing Ukraine's top prosecutor in 2016. Rudy Giuliani, one of Trump's personal lawyers, has pushed the Ukrainian government to investigate the matter.

Why is this coming up now?

Because of an intelligence community whistleblower 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 into the open when the House Intelligence Committee chairman, Rep. Adam Schiff, D-Calif., sent an angry letter to Maguire September 10 demanding the complaint be shared with his panel.

What did the whistleblower claim?

The full extent of the whistleblower's complaint, as well as the whistleblower's identity, is not publicly known because Maguire will not share it. Reporting by The New York Times and others has established that the complaint involves Trump's interactions with Ukraine and a phone call with a foreign leader — possibly, but not necessarily, Zelenskiy. It is not clear if it includes other matters.

Did Trump use US 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 delay of the aid was first publicly disclosed about a month after the July phone call between Trump and Zelenskiy. 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.

What does Trump say?

The president insists that he has been unfairly accused, saying — without offering evidence — that the whistleblower is "partisan" and that Democrats and the news media are initiating a new "witch hunt" against him. 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.

What is Giuliani's role in this?

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 Paul Manafort, Trump's 2016 campaign chairman, who is now serving a prison sentence on charges related to his Ukrainian political work. Giuliani has sought information about both subjects, and traveled to Madrid this summer for a meeting with one of Zelenskiy's top aides, whom he urged to investigate the matters.

Did Biden do something wrong?

There is no evidence that 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 US policy toward the country, and a standard condition for Western aid. On Saturday, Biden said he had never spoken with his son about any overseas work.

Biden played a lead role in the Obama administration's diplomacy with Kyiv, 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.

Written by: Michael Crowley and Kenneth P. Vogel

© 2019 THE NEW YORK TIMES