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What Are The Rules For The Senate Impeachment Trial? Here's How It'll Go

On Tuesday, Jan. 21, more than a month after the House of Representatives voted to impeach President Donald Trump, the Senate's impeachment trial officially began — and bipartisan divisions immediately took center stage. Debate over the rules for the Senate impeachment trial continued into the early hours of Wednesday morning, with the Senate's Republican majority voting down Democrats' attempts to subpoena key witnesses and documents. After hours of debate, the Senate finally voted 53 to 47 along party lines to finalize its impeachment trial rules, concluding an intense first day of proceedings.

Over the course of Tuesday's debate on trial rules, Democrats proposed 11 amendments to Senate Majority Leader Mitch McConnell's rules resolution — all of which were voted down by Republican senators. According to CNN, these proposed amendments included an attempt to subpoena key witnesses, including acting White House chief of staff Mick Mulvaney and former national security adviser John Bolton. Other proposed amendments included proposals to give senators more time to respond to motions, to subpoena officials from the White House Office of Management and Budget, and to subpoena certain records from the Department of Defense, per NBC News. All of the amendments were rejected after Republicans voted them down.

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The final resolution concerning the rules for Trump's impeachment trial did not include any of the amendments that Democrats had proposed. However, it did contain last-minute handwritten modifications from McConnell, per NBC, including notes regarding evidence admissions and the amount of time that both sides would have to make their arguments, but did not include any of the amendments that Democrats had put forward. Per the resolution, the House impeachment managers and Trump's legal team will each have 24 hours over three days — starting on Wednesday, Jan. 22 — to make their cases. This process is comparable to the prosecution and the defense making their opening arguments. After the two sides have finished making their arguments, senators will be able to ask questions "for a period of time not to exceed 16 hours," per the resolution. They must submit these questions in writing, and The New York Times predicted that this question period could take place early in the week of Jan. 27.

Following this timeframe for questions, the impeachment managers and Trump's legal team will present arguments about whether or not the Senate should subpoena witnesses or documents. At that point, the Senate will once again deliberate on this question — but unlike at the outset of the trial, when Republicans firmly rejected the notion, some GOP senators have indicated that they may be open to subpoenas at that point in the proceedings. According to Politico, four Republicans would need to break with their party for Democrats to call witnesses during the trial.

If the Senate does decide to allow subpoenas at that stage, the trial rules say all witnesses must first be deposed in writing, after which the Senate will use the depositions to decide which witnesses can testify. Finally, after all of these proceedings and deliberations are wrapped up, the Senate will take a vote on whether to acquit Trump or remove him from office.

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House impeachment managers launched their opening arguments on the afternoon of Jan. 22 in an appeal to win a few Republican senators over. Whether or not Democrats are able to subpoena key documents and witnesses, the trial proceedings nevertheless mark a historic moment.