What possible poisoning of Russia's Navalny says about Putin

Russia’s leading opposition figure is seriously ill in a Siberian hospital, the victim of a possible poisoning. Alexei Navalny is a crusading anti-corruption activist and aspiring politician who has been a thorn in President Vladimir Putin’s side for years. Nick Schifrin reports and talks to Catherine Belton, investigative correspondent for Reuters and author of a recently released book on Russia.