The rats do not want Sanders or Warren on the ballot. They know either loses in a General so the witnesses is a win win.
The issue is due process, and the democrats are not arguing for due process, just a “fair trial”. Without due process there cannot be a fair trial. A fair trial requires vetting of both witnesses and documents. That should have happened in the House impeachment, but the democrats did not want a fair trial, just to repeat the mantras in the incurious media, after repeating things of dubious veracity or even outright lies.
Adam Schiff did not testify in front of Nadler’s committee for a reason. The questions would have been brutal. There is still outstanding secret testimony with the IG.
But the bottom line has nothing to do with a fair trial using vetted witnesses and documents.
DK