We Need to Fix Our Democracy: Lawrence Lessig Weighs Presidential Run to Rid Money from Politics; Sarah Shourd, Hiker Jailed in Iran, Hails Nuclear Deal While Urging Release of Detained Americans; “Opening the Box”: After Being Jailed in Iran, Sarah Shourd Examines Solitary Confinement in U.S.; Facebook Accused of Censoring Hundreds of Prisoners by Purging Profile Pages Without Cause; In Guatemala, Protests Threaten to Unseat President, a U.S.-Backed General Implicated in Mass Murder.