Stone is known for bizarre antics that are just as often self-serving as self-destructive. (If you are unfamiliar, I highly recommend Netflix's Get Me Roger Stone.) "Politics with me isn't theatre," Stone once told the Weekly Standard. "It's performance art — sometimes, for its own sake."
Indeed, Nunberg did little to suggest Monday that this wasn't some Stone-orchestrated scene. He repeatedly talked about how he felt Mueller was targeting Stone for alleged collusion with WikiLeaks, and he repeatedly argued that Stone was innocent. Despite plenty of inconsistencies in his appearances, this was one point he kept coming back to.
"I'm not going to cooperate when they want me to come into a grand jury for them to insinuate that Roger Stone was colluding with Julian Assange," Nunberg told MSNBC. "Roger is my mentor. Roger is like family."
He added in another interview with MSNBC: "I'm not going to go in there for them to set up a case against Roger. Roger did not do anything. Roger and I were treated like crap by Donald Trump, okay?"
But even if you grant that this was all a contrived spectacle to assist Stone in some way, that still doesn't answer how. Refusing to assist Mueller would seem to be help enough; why go on a media blitz saying all kinds of bizarre things? Perhaps this was just performance art for performance art's sake.
He broke under pressure
In Nunberg's interview with CNN's Erin Burnett, Burnett asked him a question that might have otherwise seemed off-base: Are you drunk? In fact, Burnett didn't just ask; she said she smelled alcohol on his breath.
Nunberg denied he had been drinking and said he wasn't on anything "besides my meds — antidepressants".
Even separate from that question, though, it was clear Nunberg was under plenty of pressure. That tends to be the case when you've got jail time hanging over your head for ignoring a subpoena.
When New York magazine's Olivia Nuzzi reached Nunberg's mother by accident, she said his mother told her Nunberg was unavailable because "he's not doing well".
We all react to stress differently. Perhaps Nunberg, who was known for being very freewheeling and open with the media, simply started talking and couldn't stop. Maybe he found himself in a tough spot and his first reaction was to try to talk his way out of it.
His comments were targeted at Trump
Nunberg's relationship with Trump is nothing if not complicated. As CNN recaps, Trump has fired him, rehired him, fired him again and sued him for $10 million before the two of them settled a lawsuit over Nunberg's alleged breach of their nondisclosure agreement. The White House has also been dismissive of Nunberg whenever he has occasionally offered comments it didn't like.
During Monday's interviews, Nunberg oscillated between saying Trump hadn't colluded and suggesting he might have had some arrangement with Russia. He at one point said Trump was too smart to fall victim to Russian blackmail, only to later say that Trump "caused this, because he's an idiot". He also said that "there is nobody who hates [Trump] more than me."
"I'm not a Donald Trump fan, as I told you before, okay?" Nunberg told CNN. "He treated me like crap."
If Nunberg really does harbour such resentment toward Trump, maybe publicly speculating about Trump having had an arrangement with Russia and having known about the Trump Tower meeting is one final piece of revenge. Coming from someone who has been interviewed by Mueller's team, that certainly carries some weight. Maybe he wanted to suggest Trump had done something wrong while sounding like he was defending him.
Or maybe, like former chief White House strategist Stephen K. Bannon, Nunberg is truly frustrated by what Trump has done — including to him — and couldn't help himself. And maybe he even felt that Trump needed some kind of bat signal delivered through cable news about how much trouble he's in.
He was trying to impeach himself as a witness
This one comes via Post columnist Ruth Marcus, who says Nunberg has now "successfully destroyed his credibility and therefore his utility as a trial witness for Mueller. Mission accomplished?"
Indeed, if Nunberg was trying to look erratic and unreliable on Monday, mission accomplished. But would Mueller suddenly lose interest just because of this performance?