In an unprecedented exclusive interview, MSNBC Chief Legal Correspondent, Ari Melber, brings together four witnesses involved in Bob Mueller’s Russia probe. Three of the witnesses – Jerome Corsi, Sam Nunberg and Michael Caputo discuss Mueller’s interest in their relationship with Trump advisor Roger Stone and how their relationships with Stone have changed during the course of the investigation. Jerome Corsi says Stone has “intensified” his attacks on him, while Caputo suggests Corsi’s comments are “sterring” Stone “toward a perjury charge”.