1. They come up with some kind of compromise

But what would that look like, given the differences between the two sides over witnesses? Josh Chafetz, a constitutional expert at Cornell Law School, said that there are smaller things on which senators could compromise to get the trial started and that the big thing can be addressed later on. They could compromise on how long the trial should be (two weeks? six weeks?) and whether new evidence can be presented.

“In other words, witnesses/no witnesses isn’t a binary: there are a lot of smaller procedural trade-offs that can be made,” Chafetz wrote in an email to The Fix.

That still doesn’t solve the broader problem of how to break the impasse between Pelosi and McConnell over witnesses, but it’s a start.