Some commenators characterized political happenings of the past week as "block buster" news as Speaker of the House, Nancy Pelosi announced an impeachment inquiry. Article I, Section 2 of the Constitution assigns to the House the power of impeachment. This was spurred by a whistleblower report about President Trump and the conversation he had this past August with the President of Ukraine. The report is that president Trump talked about U.S. aid to Ukraine and then discussed and encouraged bringing charges against Joe Biden and his son, Hunter, for their activities related to Ukraine.
Congress operatesin a quasi-judicial capacity in the process of impeachment, which is governed by Article II, Section 4 of the Constitution, which states that the President, Vice President and all civil officers of the United States, shall be removed from office on impeachment for, and conviction of, treason, bribery, or other high crimes and misdemeanors. Remember though, that impeachment can occur without removal from office. I have found over the years that many students and perhaps most citizens think that impeachment means removal from office. A question that recurs about impeachment and creates great debate is what offenses constitute high crimes and misdemeanors that could lead to removal from office.
The Senate is given the sole power to try all impeachments, which occurs after the House prepares articles of impeachment by a majority vote. At the trial, the House acts as the prosecutor through an appointed committee of managers, and the Senate sits as a court. It's presiding officer is the Vice President, but if the impeachment proceedings are about the President, then the Chief Justice of the United States presides. Today that would be justice John Robers. This constitutional provision removes the Vice President from any conflict of interest in the outcome. Two-thirds of senators present is necessary for conviction. So far, two presidents, Bill Clinton and Andrew Johnson, have been impeached but not convicted. Andrew Johnson was saved from removal as president in 1868 by one vote, that of Senator Edmond Ross of Kansas, who is the subject of one of the profiles in courage in John F. Kennedy's book, Profiles in Courage. He had been expected to vote for conviction, so his "no vote" was a surprise.
Some other matters about impeachment: Impeachment may not be brought against members of Congress. Though "civil," they are not "officers." Impeachment actions have been brought against federal judges and some have been removed from office. Impeachment is not applicable to military officers, who are not civil officers. Also, Raoul Berger, who is the author of a major study on impeachment contends that conviction by the Senate on impeachment would be subject to review by the Supreme Court.
As matters now stand, I think that President Trump will be impeached by not convicted at a Senate trial with a Republican majority.