LIVE: Trump impeachment trial moves to next phase as senators begin questioning the prosecution and defense

Associated Press

In this image from video, Senate Majority Leader Mitch McConnell, R-Ky., speaks during the impeachment trial against President Donald Trump in the Senate at the U.S. Capitol in Washington, Tuesday, Jan. 28, 2020. (Senate Television via AP)

• The Senate on Wednesday began a 16-hour period of submitting written questions in President Donald Trump's impeachment trial.
• This comes after six marathon days of opening arguments from House impeachment managers, who act as prosecutors in the trial, and Trump's defense team.
• The question-and-answer session will be split into two eight-hour days and will likely be pivotal in helping Republican senators decide whether to join Democrats in voting to call additional witnesses to testify.
• Scroll down to watch the trial and follow Insider's live coverage.
• Visit Business Insider's homepage for more stories.

On Wednesday, senators began a 16-hour period of submitting written questions to the prosecution and the defense in President Donald Trump's impeachment trial.

The question-and-answer period comes after six marathon days of opening arguments from House impeachment managers - who act as prosecutors in the president's trial - and Trump's defense team, led by White House counsel Pat Cipollone and Trump's personal defense attorney Jay Sekulow.

After the defense rested its case on Tuesday, Senate Majority Leader Mitch McConnell announced the 16-hour question period would be spread out over two days, and encouraged Senators to keep their questions "thoughtful" and "brief."

The 16 hours during which senators submit their written questions will likely be pivotal ahead of a vote on whether the Senate will call additional witnesses to testify in Trump's trial. That vote is scheduled to take place on Friday.

The House of Representatives impeached Trump last month for abuse of power and obstruction of Congress. Both charges related to his efforts to coerce Ukraine into launching politically motivated investigations targeting former Vice President Joe Biden, a 2020 Democratic frontrunner, his son Hunter, and the Democratic Party as a whole.

While doing so, the president withheld $391 million in vital military aid to Ukraine, as well as a White House meeting that Ukrainian President Volodymyr Zelensky desperately sought and still hasn't gotten.

On Monday and Tuesday, Trump's defense team said the Senate didn't need to subpoena John Bolton, the former national security adviser, to testify in the trial after a leak of his unpublished book manuscript threw a wrench into their defense strategy.

The New York Times reported on the manuscript Sunday night, in which Bolton wrote that Trump personally told him he would withhold Ukraine's military aid until Zelensky agreed to deliver politically motivated investigations targeting the Bidens.

On Tuesday evening, multiple outlets reported that McConnell emerged from a closed-door meeting with Senate Republicans without the necessary votes to block witnesses. Senators must approve witnesses with a 51-vote majority, meaning four Republicans would need to side with Democrats to call Bolton.

Watch the trial below:

Scroll down to follow Insider's live coverage: