As I understand it Roberts can choose if the witnesses are relevant or not to the case...if in fact they vote for that motion Friday...I understand Trumps team would not agree to this saying NO!... via I think Sekulow.....
They simply shouldn’t do so Imo...this is a play by the dems big time...if they agree to Roberts being ‘the decider’ then it’s also a certainty there WILL be witnesses which shouldn’t be.......and further rules will have to be set and all the other “time stealing” tactics will come into play the Demorats are smacking their lips for.
In the Clinton trial, this was done by vote of the Senators. See The Impeachment Trial of President William Clinton, by Douglas O. Linder (2005).
Trial in the SenateNote that none of the witnesses called in the Clinton trial were senior advisors of the President who would be likely to be blocked via executive privilege.[snip]
The next day, the Senate met in a closed session to hammer out a bipartisan plan (passed on a vote of 100 to 0) for procedural rules to govern the trial. Each side would get twenty-four hours to present its case without witnesses. The Senators would then have two days for a question-and-answer session, Only after that would the Senate vote on motions to dismiss or requests for witnesses.
The House managers, who would prosecute Clinton in the Senate, plotted strategy. A key question they faced was whether to call live witnesses and, if so, how many and which ones. A preliminary list drawn up included many names: the judge in Jones case, Susan Weber Wright, Monica Lewinsky, Secret Service agents, Kathleen Willey (a White House volunteer who claimed to have been groped by Clinton), Vernon Jordan, various Clinton aides, and even New York mayor Rudy Giuliani (who, as a former U. S. attorney, could address the subject of prosecutions of public officials). Senate Majority Leader Trent Lott, and Minority Leader Tom Daschle, were not, however, thrilled at the prospect of live witnesses. They saw live witnesses as a threat to their desire to stage a speedy and dignified trial that would not become an embarrassing national spectacle. Both leaders understood that the prospects of at least a dozen Democratic Senators voting to convict, the minimum necessary for the required two-thirds vote, were exceedingly slim--barring some new shocking revelation about the President's conduct.
[snip]
The day after the question-and-answer period, Monica Lewinsky, having been ordered to fly from Los Angeles to Washington to meet with the House managers, reluctantly appeared at the Capitol's Mayflower Hotel to discuss with three congressman her possible testimony in the Senate trial. Lewinsky was worried, telling a friend: "I'm nervous about what he'll [Starr] will do to me if he doesn't get what he wants." Lewinsky, after receiving assurances that her answers were covered by her immunity agreement, answered the managers' questions. The questions ranged from why she kept her stained dress (it made her look fat) to what she thought should happen to Clinton ("I think he should be censured but not removed"). The managers concluded from their interview that Lewinsky would make a great live witness. They narrowed their wish list of witnesses to three: Lewinsky,Vernon Jordan, and Sidney Blumenthal. The media frenzy surrounding Lewinsky's return to Washington, however, was giving some Republican senators second thoughts about whether they wanted her or any other live trial witnesses.
[snip]
Over the first three days in February, House managers deposed Lewinsky, Jordan, and Blumenthal. Lewinsky's deposition took place in a hotel suite before a throng of over forty attorneys and congressional aides. Under Congressman Edward Bryant's inartful questioning, she proved a dominating and unhelpful witnesses, often answering with just a "yes" or a "no." She described her present feelings toward the President as "mixed" and claimed that she filed her false affidavit in the Jones case for her own interests, not Clinton's. Most observers left the deposition believing that Lewinsky was no victim. Tom Griffin, the Senate's chief lawyer, having witnessed the deposition, described it to Trent Lott as "a disaster."
Support for live witnesses collapsed after the Lewinsky deposition. The Senate voted 70 to 30 against issuing Lewinsky a subpoena to testify. Instead, on a 62 to 38 vote, the Senate authorized each side to show video excerpts of deposition testimony by each of the three witnesses. On February 6, the managers projected video images of Lewinsky, Jordan, and Blumenthal on four flat screens at the front of the chamber. Clinton's lawyers did the same, offering an uninterrupted twenty-minute clip of Lewinsky that showed her intelligence and near total control of her questioner.
Also note that it was the Senate, via voting, that made all the decisions. It was NOT the Chief Justice in any way making decisions regarding the admissibility of witnesses.
-PJ