Growing numbers of Democrats are calling for the impeachment of US President Donald Trump over allegations that he sought political dirt on his potential 2020 presidential rival, Joe Biden.

This is what we know about the affair launched by a complaint from a mysterious whistle-blower in the US intelligence community.

The phone call 

The political scandal stems from a July 25 telephone call between Trump and Ukraine’s newly elected President Volodymyr Zelensky, a former comedian who ran for office as an anti-corruption crusader and reformer.

Trump has acknowledged urging Zelensky during the call to investigate the business dealings in Ukraine of Hunter Biden, the son of Joe Biden, who is leading Trump in 2020 election polls.

The Wall Street Journal said Trump urged Zelensky “about eight times” during the call to work with Rudy Giuliani, his personal attorney, on a probe into Hunter Biden.

Democrats in the House of Representatives accused Trump and Giuliani of trying to coerce Ukraine, in exchange for military assistance, into conducting a “politically motivated” investigation into Hunter Biden, a move they said would represent a “staggering abuse of power.”

Three Democratic-controlled House committees demanded that the White House turn over a transcript of the call and Trump has indicated that he would be happy if it were made public.

US military aid for Ukraine

According to The Washington Post, about a week before the phone call with Zelensky, Trump told his acting White House chief of staff, Mick Mulvaney, to hold up a package of nearly $400-million in military aid for Ukraine, which is battling pro-Russian separatists.

Trump has denied dangling the military aid in exchange for a probe into the son of his main political rival and the Journal said he did not specifically mention the assistance during the conversation.

“I didn’t do that at all,” Trump told reporters. “I did not make a statement that you have to do this or I’m not going to give you ‘A.’”

“With that being said,” the president continued, “you want to see a country that’s going to be not corrupt.”

Hunter Biden

Hunter Biden served from April 2014 to April 2019 on the board of Burisma Holdings, a Ukrainian gas firm accused of corrupt practices, but he has not been personally accused of any wrongdoing.

As Barack Obama’s vice president, Joe Biden and other Western leaders pressured Ukraine to get rid of the country’s top prosecutor, Viktor Shokin, because he was seen as not tough enough on corruption.

Trump has claimed that Biden, in seeking the removal of Shokin, was seeking to protect his son but that allegation has largely been debunked and there has been no evidence of illegal conduct in Ukraine by the Bidens.

Whistle-blower

On August 12, an unknown whistle-blower in the US intelligence community filed a complaint with Michael Atkinson, the Inspector General of the Intelligence Community (ICIG), regarding a matter of “urgent concern.”

After reviewing the complaint, Atkinson determined it was “credible” and forwarded it on August 26 to the acting Director of National Intelligence, Joseph Maguire, a Trump appointee.

The Democratic-led House Intelligence Committee is demanding that the whistle-blower’s complaint be turned over but Maguire has declined to share it.

According to The Washington Post, the complaint concerned a “promise” Trump made in a phone call with a foreign leader, widely reported to be the July 25 conversation with Zelensky.

Impeachment

More than 150 of the 235 Democratic members of the 435-seat US House of Representatives have come out in favour of impeachment or the opening of an impeachment inquiry against Trump for abuse of power.

A president can be impeached by a simple majority of the House.

The case would then be sent to the Republican-controlled Senate, where a two-thirds majority is necessary to remove a president from office. 

No Republicans have come out in favour of impeachment.

Nancy Pelosi, the Democratic speaker of the House, has been reluctant to embrace impeachment so far but pressure has been building on the lawmaker from California to go down that road.

Trump on Tuesday said calls for his impeachment were “ridiculous.”

“It’s a witch hunt,” he said.

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