The Hill reports:
The organizing resolution for President Trump’s impeachment trial will require that senators debate and vote on a motion to subpoena additional witnesses but not on a motion to dismiss articles of impeachment, say GOP senators who have viewed the resolution.
Language to require a debate and vote on witnesses after the House impeachment managers and Trump’s lawyers have made their arguments was strongly supported by Sen. Susan Collins (R-Maine), who has come under pressure from Democrats.
Senators would have been able to make motions to subpoena additional witnesses after phase one of the trial — and Senate Democrats have pledged to force such votes — but Collins’s language now formally ensures that the debate and vote will happen.