In an email to Republican colleagues on Saturday morning that was obtained by Politico, Mr McConnell said that he would vote to acquit Mr Trump, writing: “As I have said for some time, today’s vote is a vote of conscience and I know we will all treat it as such.
“I have been asked directly by a number of you how I intend to vote, so I thought it right to make that known prior to the vote. While a close call, I am persuaded that impeachments are a tool primary of removal and we therefore lack jurisdiction.”
Mr McConnell then confirmed which way he would vote, writing: “I will vote to acquit.”
Mr Trump’s Senate trial began on 9 February, just a few weeks after the House voted to impeach him for inciting the deadly Capitol riots on 6 January with a speech at a “Save America” rally near the White House.
Five people died and several more were injured as a mob of pro-Trump supporters breached the Capitol on that day. A week later, and a week before leaving office, Mr Trump was impeached by the House.
In his email on Saturday, Mr McConnell also indicated that the former president could still face criminal prosecution for his actions during the riots, saying that the possibility “alleviates the otherwise troubling ‘January exception’ argument raised by the house.”
Although he has criticised Mr Trump’s actions over the last few weeks, Mr McConnell had refused to say which way he would vote on impeachment.
He voted alongside 43 other Senate Republicans earlier in the week that Mr Trump’s trial is unconstitutional, but still did not confirm which way he would vote on conviction after the proceedings went ahead.
However, the former Trump ally finally confirmed that he will vote to acquit on Saturday morning, just hours after Mr Trump’s legal team concluded its defense.
Speaking to Politico about Mr McConnell’s confirmation on Saturday, Republican senator Roy Blunt said: “Based on his comments over the past two months I really had no idea what he was going to do.”
The Missouri senator added: “He said everybody should make this decision and their own and I guess he thought that that would apply to him as well.”
After only using three of the 16 hours allowed to mount its defense on Friday, Mr Trump’s legal team had been pushing for the conviction vote to take place on Saturday, but that plan was derailed after Democrats insisted on witnesses being called.
Five Republicans — Mitt Romney of Utah, Susan Collins of Maine, Lisa Murkowski of Alaska, and Lindsey Graham of South Carolina — also voted to allow the impeachment managers and Mr Trump’s defense counsel to call witnesses.
Mr Trump is not expected to be convicted, as some 17 Republicans would need to join all 48 Democrats and two Independents to meet the two-thirds’ threshold. Only six GOP senators have signaled that they will vote for conviction.
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