KEY POINTS
  • A breakdown in the deal between former Trump campaign chief Paul Manafort and special counsel Robert Mueller suggests prosecutors believe they were told substantial lies, according to law enforcement experts.
  • On Monday, attorneys for the special counsel accused Manafort of lying to the FBI after the plea agreement was struck.
  • "It has to be a pretty big deal," said Stephanie Douglas, a 24-year FBI veteran and a former senior official in the bureau's national security branch. "It's not that he lied about the color of a jacket that he wore to a meeting."
Former Trump campaign manager Paul Manafort departs from U.S. District Court in Washington, U.S., February 28, 2018.

A breakdown in the cooperation agreement between former Trump campaign chief Paul Manafort and special counsel Robert Mueller suggests prosecutors believe Manafort told them substantial lies, law enforcement experts said.

On Monday, attorneys for Manafort and the special counsel called off a cooperation deal that had been in place since Manafort pleaded guilty to a range of financial crimes in September. The special counsel office said in a court filing that Manafort had lied "on a variety of subject matters" after the deal was struck, and it promised to provide details to the court before Manafort's sentencing.