In the United States, the impeachment inquiry against Donald Trump - only the fourth president to face such an investigation - has become the most talked about issue in Washington. At the centre of it is a phone conversation in which president Trump allegedly solicited the help of the Ukrainian president to undermine a political rival. Nancy Pelosi, the speaker of the Democratic Party controlled lower house of Congress, says that it had to initiate the impeachment investigation because it could not "ignore what the president did". But is there such a thing as a fair and objective way to impeach a president? How important is the court of public opinion and what do events say about America's political divide? Plus, what are the lessons from history? Paul Henley and a panel of expert guests discuss what it takes and what stands in the way of removing an American president from office.

(Photo: A demonstrator showing support for an impeachment hearing in New York. Credit: Lucas Jackson/Reuters)