The trial of Paul Manafort has not focused on President Donald Trump, but it has provided a lens through which to view the special counsel’s investigation.

Rick Gates, Trump’s former deputy campaign chairman, testified as a government witness in the ongoing trial of Manafort, who has been charged with tax and bank fraud. Gates, who worked for Manafort for years, pleaded guilty in the Eastern District of Virginia to charges of conspiracy and lying to the FBI. As part of his plea deal, Gates agreed to cooperate against Manafort, who served as Trump’s campaign manager in 2016.

During the trial, Gates spent several hours over the course of three days on the witness stand, describing how he worked with Manafort to hide money in offshore bank accounts to avoid paying taxes on $16 million in income. Gates also detailed Manafort’s various schemes to defraud banks when his political consulting business dried up and he became desperate for cash.

In light of Gates’ plea deal, it was no surprise that Gates was testifying against Manafort in this case, and he likely will do the same in a second federal case that is pending against Manafort in the District of Columbia.

But the real intrigue came during the cross-examination of Gates. After answering a number of questions about his own misconduct, including embezzling hundreds of thousands of dollars from Manafort, Gates was asked if he had been questioned by the special counsel’s office about his time on the Trump campaign. When Gates answered “yes,” he then was asked whether he had been interviewed several times about his time on the Trump campaign. Before Gates could answer, the government objected, and the parties conferred with the judge at sidebar. When questioning resumed, defense counsel moved on to a new line of questioning. The next morning, the government filed a motion to seal the portion of the transcript reflecting the conversation that occurred at the sidebar conference. In the motion, the government argued that disclosure of the transcript would reveal “substantive evidence pertaining to an ongoing investigation.” The court granted the motion to seal that portion of the transcript until that information becomes public “if that were to occur.”

Despite the secrecy, the incident was still revealing. The government’s use of the terms “substantive evidence” and “ongoing investigation” suggests that Gates’ cooperation exceeds the scope of the case currently on trial and the other case against Manafort that is already pending in the District of Columbia. Gates testified at trial that he has met with the FBI more than 20 times.

In my experience as a former federal prosecutor, debriefing sessions with cooperating defendants can be wide-ranging, including portions where the cooperator volunteers information. At other times, investigators ask cooperators their own questions. In both instances, investigators attempt to test the veracity of the cooperator’s statements by comparing them to other evidence. Agents and prosecutors may then come back to the cooperator and confront him with inconsistencies. Sometimes a defendant will lie to investigators before getting fully on board as a cooperator. Such lies must be disclosed to the defense in any case in which the cooperator is going to testify. With Gates, he initially lied to the FBI, and then ultimately pleaded guilty for doing so and separately admitted to conspiracy.

From the government’s objection and motion to seal, it appears that Gates, during his 20 meetings with the FBI, may have provided information beyond the Manafort cases. It may be that the FBI will only use this information to develop a lead in the investigation, or it may be that this is only the first of many trials for Gates as a witness.

Gates’ plea agreement states that he shall cooperate with the special counsel in “any and all matters as to which this Office deems the cooperation relevant.” The United States Attorneys Manual, which provides policy guidance for federal prosecutors, requires cooperators to provide “substantial assistance” in the investigation or prosecution of another to receive a recommendation for a reduced sentence. Substantial assistance credit may also be given to a defendant who provides valuable intelligence information. This information need not result in a criminal charge against another defendant if the government assesses that the information has value for the intelligence community.

It is unknown exactly what Gates has told the FBI, but his roles as deputy campaign manager and later deputy chairman of Trump’s inaugural committee put him in positions to see and hear what was happening at a high level as Trump ran for president and then transitioned to the White House. Gates also spent time in Ukraine, working with Manafort and his business associate Konstantin Kilimnik, whom the special counsel has alleged to be a former Russian intelligence officer. Gates potentially has information of great value to Special Counsel Robert Mueller that is relevant to his mandate to investigate links between the Trump campaign and Russia.

The plea agreement also permits Gates’ attorney to argue for a sentence of probation if Gates continues to cooperate and provide truthful testimony. The plea agreement goes on to state that, “Depending on the precise nature of the defendant’s assistance, the Office may not oppose defendant’s application.” In light of the significant tax and bank fraud crimes with which Gates was originally charged, a sentence of probation seems extremely generous in exchange for his testimony about Manafort. Generally, the more information a defendant can provide, the more generous is the reward. Is the potential reduction so great here because Gates is providing additional information of significant value beyond testimony against Manafort?

It may be that Gates received such a good deal because the special counsel’s office wanted to use Gates to induce Manafort to cooperate, but so far, Manafort has not budged.

The strength of the government’s evidence, revealed in full in court, now makes it seem even more curious that Manafort would choose to go to trial rather than work out a plea deal. While a jury can always decide to acquit, any objective lawyer assessing the evidence to date would conclude that a conviction in this case is likely. Even if Gates was an unlikeable witness because of his own wrongdoing, his testimony was corroborated by hundreds of documentary exhibits, including tax returns, corporate documents, bank records and email messages. In cases where evidence of guilt is this strong, defense counsel usually seeks a plea deal to reduce his client’s potential sentence in exchange for cooperation. In light of his role as Trump’s campaign chairman, Manafort no doubt has information that is valuable to the special counsel. At the very least, Manafort could shed light on what really happened at the Trump Tower meeting in June 2016, for which there are multiple conflicting stories from various participants. Manafort’s decision to go to trial instead could mean that he is betting against the odds or even hoping for a pardon.

Or it may be that Manafort is waiting to see how this trial comes out before he decides to cooperate. If Manafort were convicted in the Eastern District of Virginia case, and then approached the special counsel about cooperating, he likely could negotiate a plea deal that covered both trials. So, it could still happen.

The question now is whether additional charges will emerge from Gates’ cooperation with the government in the “ongoing investigation.”

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