History may show that Monday ranks among the most consequential days yet of Robert Mueller’s 18-month special counsel investigation into Russian interference in the 2016 presidential election.

As George Papadopoulos, one of the most enigmatic characters to emerge in Mueller’s investigation, reported to a Wisconsin prison Monday, a confluence of small developments may indicate that by the time he emerges from Federal Correctional Institute Oxford two weeks from now, we might know far more about the breadth of Russia's efforts—and the Trump campaign's ties to them—than we do now.

In fact, as the holiday season begins to unfold, it’s clear that Mueller knows who’s been naughty and who’s been nice.

Paul Manafort, for one, is topping the naughty list.

The 'Mueller Report'

A report Tuesday in The Guardian claims that Manafort met with WikiLeaks founder Julian Assange a few months before the group leaked the hacked emails of Hillary Clinton campaign chair John Podesta. It's a potentially explosive revelation, one that Manafort has denied. " I have never met Julian Assange or anyone connected to him. I have never been contacted by anyone connected to Wikileaks, either directly or indirectly. I have never reached out to Assange or Wikileaks on any matter," Manafort said in an emailed statement.

But even before that item, Manafort might have unwittingly given Mueller just the opportunity he requires to make public even more details about the former Trump campaign chair, Russia, and the Trump campaign’s activities in 2016. In a court filing Monday, Mueller's team alleged that Manafort had lied to investigators, asking the judge to move immediately to sentencing. They also said they would provide a “detailed sentencing submission,” outlining “the nature of the defendant’s crimes and lies.”

In other words, Mueller plans to quickly issue a “report” on Manafort’s activities, one that—if it’s anything like every other court document Mueller has filed—will be more informed, more knowledgeable, and more detailed than anyone anticipates.

He’s been writing the long-anticipated “Mueller Report” bit by bit, in public, since his very first court filing.

That Paul Manafort may have been caught lying again is hardly surprising: The core of the underlying charges against him—like bank fraud and tax fraud—stem from years of lies to the IRS, the government, and financial institutions. What is surprising about Manafort’s apparent misbehavior, though, is the extent to which he seemingly never internalized just how much Mueller knows. The special counsel has apparently caught Manafort twice already in embarrassing lies: When he tried to deny ghostwriting an op-ed supporting himself, prosecutors showed the court the Microsoft Word track changes edits he’d made; when he tried to align his story with a witness, Mueller’s team hit him with witness tampering charges and showed the court his encrypted text messaging conversations.

Nor is it surprising that Mueller would potentially seize the opportunity of Manafort’s plea agreement violation to introduce all manner of evidence about his misdeeds.

In fact, such a move would be entirely consistent with one of the most surprising and least noticed aspects of Mueller’s approach all along: He’s been writing the long-anticipated “Mueller Report” bit by bit, in public, since his very first court filing.

Those waiting for Mueller to issue some massive, 9/11 Commission–style report at the end of the investigation often overlook the sheer volume of detailed information Mueller has pushed into public view already. Nearly every court document he has filed has been what lawyers call a “speaking indictment,” going into deeper detail and at greater length than is strictly needed to make the case for the criminal behavior charged.

Similarly, his “criminal informations,” the indictment-like documents filed as part of guilty pleas, have often included extraneous evidence of additional, formally uncharged criminality. In former national security adviser Michael Flynn’s plea agreement, Mueller detailed how Flynn served as an unregistered foreign agent for the government of Turkey. Manafort’s criminal information—a document that often is only a few pages, the bare minimum that prosecutors and a defendant will agree upon—this fall stretched to nearly 40 pages, including voluminous details about the so-called Hapsburg group, European politicians enlisted in Manafort’s alleged scheme, information that hadn’t appeared in any of the indictments or charges against Manafort until that point.