The sole power of impeachment belongs to the house. Can the house “punt” to the Senate to complete the impeachment process? That is exactly what is happening now. If the Senate calls witnesses to further the impeachment are they not usurping the house’s “sole impeachment” power? Do they even have the Constitutional authority to do so? Or, does separation of powers (between the house and Senate re; impeachment) preclude the Senate from doing so?
The Senate’s “sole power” is to try the impeachment the house sends to them, not to seek out new impeachable evidence or testimony. Think about an actual trial. The prosecution makes a charge, they put forward their evidence, they publish their witnesses. They are not allowed to bring in new evidence or witnesses. That is what we consider under “due process” to be a “fair trial”. The prosecution gets ONE bite of the apple, not two. The defense has the right to depose any witness the prosecution brings forward. Witnesses who’s testimony is not vetted or uncertain are objected to and not allowed. It is the prosecutions job to vet the witnesses it brings forward, not the courts.
The defense can bring in its own witnesses. Put forward their own theories. The prosecution has little power to prevent it. Some defenses are not allowed, generally however that is rare if it’s even remotely theoretically possible that the defense may be valid under some odd circumstance. The prosecution cab then call new witnesses to rebut the defenses assertions. But ONLY to rebut the defenses assertions, not to introduce new evidence or testimony previously not entered. That is what we have always considered a “fair trial”
Since when does a “fair trial” consist of the prosecution being allowed to fish for new evidence during a trial? This impeachment has turned due process on its head. Now it seems a fair trial means the prosecution gets to enter new evidence and testimony after the trial begins. Evidence and testimony the defense has no opportunity to see or plan for.
In the interest of “due process” and a “fair trial”, the Senate should open the trial, hear the opening arguments and when it comes to “witnesses” agree to hear from any witness the house has already vetted in their depositions and hearings. If the house wants new witnesses the Senate should suspend the trial and give the house time subpenae the witnesses to the house, depose them, hold hearings and vote whether to include their testimony in their impeachment case; thereby, forcing the house to do its own work.
As things stand, the house wants the Senate to call witness to provide impeaching evidence, not as trial witnesses who would have and should have been vetted pre trial. The Senate should not agree to allow any witness that would not be allowed in any normal trial. To do so is a usurpation of the houses sole impeachment power and imo would be wholly unconstitutional.