In this conversation first recorded for Washington Post Live on April 17, CNN senior Supreme Court analyst Joan Biskupic discusses her new book, “Nine Black Robes: Inside the Supreme Court’s Drive to the Right and Its Historic Consequences,” which explores the rise of the court’s 6-3 conservative supermajority, the role of the Federalist Society in shaping it, and the complicated roles of Chief Justice John Roberts and Justice Brett Kavanaugh.