When news broke late Tuesday night about how Manafort's lawyers were still talking to Trump's lawyers after Manafort pleaded guilty, many of us shook our heads. It was well known that the two teams had what is known as a "joint defense agreement" or JDA. A JDA, simply put, is an agreement between parties with a "shared interest" to share privileged information without waiving their right to assert attorney–client privilege. The big question is this: once one of the parties has their case resolved, though a trial or a plea agreement, does the JDA become null and void?

Ken Dilanian was on MSNBC this morning covering this very topic:

"It's so unusual that most lawyers have never heard of anything like it. One person said she had only seen it in organized crime cases. It's interesting, I've been reading through Paul Manafort's plea agreement, and there's no stipulation that he shouldn't be sharing secret information with some of the subjects of the investigation. Maybe they thought that was implied. What's interesting here is that Rudy Giuliani, Donald Trump's lawyer has been saying there's a joint defense agreement.

The thing about that legal experts tell me is that as soon as Paul Manafort began cooperating with Robert Mueller that joint defense agreement was null and void. They no longer have a common legal interest. What does that mean? That means these conversations between Manafort's lawyers and Trump's lawyers are no longer subject to the attorney-client privilege. in theory, Robert Mueller, if he thought there was something amiss, could call these guys before the grand jury and demand they testify under oath about what was what was said. For example, did they dangle a pardon? The bottom line is we're not sure how much of a blow this is to the Mueller investigation because we don't know at what point Mueller learned this is happening."