Betsy Woodruff in the Daily Beast says that Robert Mueller is expected to file what's called a superseding indictment against Paul Manafort and Rick Gates, his business partner.

“I would expect a superseding indictment to come down relatively soon,” said Jonathan Turley, a professor at George Washington University’s law school.

“There was much in the narrative of the indictment that referenced crimes not charged,” he added. “Prosecutors will often issue a superseding indictment as the grand jury continues its work. There’s also a tactical reason for this, that superseding indictments tend to grind defendants a bit more over time.”

A superseding indictment would essentially replace the current indictment of Manafort. And in that current indictment, Mueller’s team hinted there was more to come. In particular, they hinted at potential tax charges for Manafort’s foreign financial transactions. Federal prosecutors can bring charges against any American who has money in a foreign bank account and doesn’t check a box on their tax forms disclosing it. The Manafort/Gates indictment describes financial behavior that may be liable for that kind of prosecution. And that’s an indicator that Mueller’s team may be preparing to formally charge both men with violating tax laws.

Seems like Manafort has not agreed to cooperate with Mueller, so the special counsel is turning up the pressure on Trump's former campaign chair. Will it work?