His side: Peter Strzok speaks

In the summer of 2016 FBI Special Agent Peter Strzok led the bureau's investigation into the Trump campaign's connections with Russian officials, which brought forth criminal convictions of Paul Manafort and George Papadopoulos; Michael Flynn also plead guilty for lying to the FBI. But Strzok's personal conduct also led to his dismissal from the FBI, and raised questions over the integrity of his work. CBS News national security correspondent David Martin sits down with Strzok, author of the new book, "Compromised: Counterintelligence and the Threat of Donald J. Trump."