One of the prosecutors who brought the case against Scooter Libby says President Trump's pardon of the ex-top aide to former Vice President Dick Cheney sends a not-so-subtle message to potential witnesses in special counsel Robert Mueller’s Russia investigation.
Rachel Maddow shows how Robert Mueller has worked with other departments and agencies in the course of the Trump Russia investigation, ensuring that even if the special counsel is fired, the elements of the investigation live on.