Sign up for the MSNBC newsletter
You have been successfully added to our newsletter.
Let our news meet your inbox
Was Tamerlan the mastermind and Dzhokhar 'brainwashed'?
The Huffington Post's Ryan Grim, the Grio's Joy Reid, BBC's Katty Kay and the National Journal's Ron Fournier join Alex Wagner for the latest updates in the investigation into the Boston Marathon bombings. NBC News' Pete Williams reports.