Mueller said in the joint status report filed on Monday that because Manafort had violated the plea agreement, their cooperation was over and the judge should move forward with sentencing. In failing to fully cooperate with Mueller, Manafort appears to have risked additional charges and harsher sentencing, which wouldn’t matter if Trump issues a pardon. But Manafort could still be vulnerable to prosecution at the state level, like in New York for tax fraud, and his guilty pleas related to filing false tax returns would likely be used against him.

On the one hand, the collapse of the plea agreement could be a setback for Mueller, who may have been counting on Manafort to confirm missing details that the special counsel needs to potentially secure future indictments. But the fact that Mueller even knew Manafort was lying at all—he intends to detail exactly how he knew in a forthcoming report—shows that the special counsel may already know more than we think. Trump, moreover, submitted his written answers to Mueller last week. If any of Trump’s answers line up with Manafort’s allegedly false statements, Mueller could accuse him of misleading investigators.

Legal experts called Manafort’s arrangement “extremely unusual”—and potentially unethical depending on what was discussed between Manafort’s lawyer and Trump’s team. Alex Whiting, a former federal prosecutor in Washington, D.C., and Boston who focused on organized crime and corruption cases, told me that if Manafort approved of his lawyers sharing information with Trump, then he never fully aligned his interests with the government—and was therefore never fully serious about cooperating. “I think it’s likely that … it was all a game to buy time, to obstruct the investigation, and perhaps even to find out more about the investigation,” Whiting said.

Former federal prosecutors turned defense attorneys told me earlier this year that joint defense agreements are common in multi-defendant cases like Mueller’s probe, which has embroiled dozens of White House staffers, Trump-campaign advisers, and associates of the president. Essentially, they said, these agreements allow defendants to get their stories straight. But once a defendant signs a plea agreement, it is typically in the defendant’s interest to coordinate exclusively with prosecutors so as to secure a lighter sentence.

The former national-security adviser Michael Flynn, for example, who pleaded guilty last December to lying to federal agents, stopped sharing information with the president’s lawyers in November 2017, as The New York Times reported. It was perceived as an early sign that he had decided to start cooperating with Mueller. The Manafort associate Rick Gates, who has been cooperating with Mueller since February, never entered into a joint defense agreement with Trump, according to his lawyer. And Trump’s longtime personal lawyer Michael Cohen, who has been cooperating with Mueller for months, has not been sharing information with Trump, either. His lawyer Lanny Davis has said publicly that Cohen has completely turned on the president and would not accept a presidential pardon.