is this john dean 2.0? >> he could be if he has incriminating information about donald trump that could be corroborated and proved. that's what happened with john dean. john dean became the principle witness establishing there was a watergate cover-up, then his testimony was vindicated when the white house tapes came out. i don't know what michael cohen knows. i don't know if he knows anything incriminating about donald trump. he hasn't said anything incriminating so far. certainly this is a tantalizing suggestion by people close to him, but it doesn't prove anything in and of itself. >> carrie, you've dealt as a prosecutor with a lot of witnesses, i imagine, and people have changes of heart for different reasons. michael cohen has been unabashedly president trump's biggest supporter for years. called him the greatest president in u.s. history. now he's changing his tune. what would cause someone to do that? he's afraid to go to jail? >> well, the motivation for mike