A new and exclusive CNN investigation from Correspondent Nima Elbagir reveals precisely what happened in Nigeria last month, when thousands protested against police brutality. Then, author Thomas E. Ricks speaks to Christiane Amanpour about his book, “First Principles.” Vox Co-founder Matthew Yglesias talks to Walter Isaacson about the importance of ideological diversity in the media business.  To learn more about how CNN protects listener privacy, visit cnn.com/privacyLearn more about your ad choices. Visit podcastchoices.com/adchoices