Update: This trial balloon appear to have popped. Senate Minority Leader Charles Schumer (D-N.Y.) on Wednesday afternoon threw cold water on the idea of swapping Hunter Biden’s testimony for John Bolton, saying “I think that’s off the table.” House impeachment manager Rep. Adam Schiff (D-Calif.) earlier likened the idea to a “fantasy football trade” and said it would allow for the process to be “abused” by Republicans.

And now Joe Biden has said no, too. “The reason I would not make the deal -- the bottom line is, this is a constitutional issue,” he said in Iowa. "We’re not going to turn it into a farce or political theater. I want no part of that.”

The original post follows:

There was no resolution Tuesday to the question of new witnesses in President Trump’s impeachment trial. As expected, Republicans clung to their stance that such questions should wait until later in the trial, while Democrats tried in vain to force the issue at the outset.

But even as all that was taking place, an idea was creeping into some Democrats’ minds: What if they traded Biden for Bolton?

The idea of a witness swap isn’t completely new, but it is nearing decision time. And as The Post’s Rachael Bade, Robert Costa and Seung Min Kim report, some Democrats are interested in perhaps calling the GOP’s bluff on the idea and perhaps offering up Hunter Biden — or his dad, Joe Biden — in exchange for the testimony of John Bolton, Trump’s former national security adviser. The idea is essentially that Bolton, who witnesses say described the Ukraine scandal as a “drug deal,” would be worth whatever pain might come from a Biden testifying:

Publicly, most Democrats have scoffed at the growing GOP clamor to hear former vice president Joe Biden’s son [Hunter] testify, dismissing him as irrelevant to the charges against Trump and accusing Republicans of trying to distract from the allegations against the president.
But behind closed doors, a small group of Democratic senators and aides has begun to question that logic, sounding out colleagues on whether to back a witness deal that could lead to testimony from former national security adviser John Bolton or other administration officials with possible firsthand knowledge of the Ukraine controversy, according to multiple Democratic officials who spoke on the condition of anonymity to describe the private discussions.
These Democrats said they believe having Hunter — or possibly Joe Biden — testify could backfire on Trump and the GOP, giving Biden and the party a platform to strike back and paint Republicans and the White House as obsessed with trying to damage one of Trump’s 2020 presidential rivals.

The first thing we can say is that this last part might be a bit fanciful. All President Trump has wanted from the start in his Ukraine efforts, after all, is to lift up the very imaginative allegation that Joe Biden did something wrong with regard to Ukraine. Having him or Hunter Biden testify extensively about the issue would hardly be a walk in the park. It would raise that issue, in fact, right before Democrats begin to formally decide whether to pick Joe Biden as their nominee. And if Trump’s idea in the first place was to prevent Joe Biden’s nomination, what better way?

The elder Biden also hasn’t quite handled this situation with aplomb. He has gotten angry when confronted with the mere idea of impropriety. He has acknowledged that perhaps it wasn’t a great idea for his son to work for the company, Burisma Holdings, and top State Department official George Kent has testified that he raised concerns about it, only to be ignored. None of this, mind you, points to wrongdoing by the candidate himself, but it’s not exactly something he wants to talk about — and obviously so.

As for Hunter Biden testifying? That’s a Pandora’s box. He’s not a politician and hasn’t been in the public limelight. The GOP could try to make this about his messy personal life and trip him up, forcing him to say something — it’s not clear what — that might hurt his dad’s candidacy. And that, again, could satisfy everything Trump wanted out of all this. Democrats might reason that Hunter Biden could be something of a sacrificial lamb and that the testimony wouldn’t touch his dad, but you just never know.

There is also a real question about whether Democrats even need to make such a swap. If they can get four Senate Republicans to cross over, they have enough votes to subpoena Bolton. Three — Sens. Mitt Romney (R-Utah), Susan Collins (R-Maine) and Lisa Murkowski (R-Alaska) — have signaled an openness to having new witnesses testify, while a fourth — Sen. Lamar Alexander (R-Tenn.) — has said he would at least vote for the ability to call new witnesses.

And now, an argument for why the swap might make sense, particularly for Joe Biden to testify: Biden is, as mentioned, on the eve of asking voters for the Democratic nomination. What better argument to make to them than that he took one for the team — that he went to Capitol Hill and withstood Republicans’ questions in the name of getting the fuller version of the truth from Bolton? If Biden thinks he can handle himself and that he has nothing to hide, there’s an argument to be made that it could accrue to his benefit. Add on top of that the fact that it’s still nine-plus months until the election — time during which lesser subplots in the Ukraine matter will inevitably fade — and maybe there’s an argument that there’s more upside in the short term (the primaries) than the long term (the general election) for Biden.

Which then brings us to Bolton. He’s the reward for Democrats in this potential swap. But how much of a reward might it be? We know, according to his own lawyer, that he was involved in “many relevant meetings” that other witnesses, at least as of early in the House’s impeachment inquiry, had not yet testified to. We know witnesses say he referred to the Ukraine situation as a “drug deal” and encouraged them to stay away from it and memorialize their concerns. We know he has said proactively that he is willing to testify, suggesting that he is a motivated witness.

But would his testimony be the silver bullet that Democrats hope it will be? If Bolton can walk in there and connect Trump directly to a Ukraine quid pro quo, perhaps. But we don’t know how directly he engaged with Trump on this matter. He was Trump’s national security adviser, but he was also somewhat on the outs with Trump during his final months on the job. He’s almost certainly not as intimately engaged in these things as acting White House chief of staff Mick Mulvaney and Trump’s personal lawyer Rudolph W. Giuliani. And no matter how much motivation he might have to spill the beans, he, just like every other witness, might feel reluctant to become the John Dean of the Ukraine scandal. He’s got a career to watch out for, after all. And if Trump isn’t removed from office and wins reelection, Bolton could become a pariah.

As I’ve argued, the counterpoint to that is the idea that Bolton, unlike most others who have wound up at the top of Trump’s administration, seems to have true convictions when it comes to policy and principle that may outweigh his personal ambition. The fact that he apparently objected so strongly — even privately — suggests he truly believes this was inappropriate. And he has been among the foremost hawks in the Republican foreign policy establishment for years — at a time when Trump appears to be attempting a more dovish turn in U.S. foreign policy (Qasem Soleimani’s killing notwithstanding). Perhaps he will feel less loyalty to Trump because of that.

But we don’t really know what Bolton would say, and he has not exactly been Democrats’ ally during his time in public life. Investing in a Biden-for-Bolton swap would be placing a heavy bet on a guy with whom Democrats probably never imagined they would align.

The upside is that Bolton could potentially dislodge some hardened views of the Ukraine scandal and contradict some of the Trump team’s defenses, while the downside is that it could torpedo Biden’s campaign. The real question here is whether Democrats are willing to risk the latter — perhaps because they feel strongly enough that Bernie Sanders or Elizabeth Warren could carry the torch if things go badly — in service of the unknown that is the former.