This weekend, Soledad O’Brien speaks with former CDC researcher Dr. Mark Rosenberg about the lack of federal gun research. He explains how research can be done without restricting weapons. Then, the federal government is reopening the investigation into the 1955 murder of Emmett Till after finding “new information.” Matter of Fact takes an inside look at what happened and speaks with a witness who says he was never interviewed by authorities. And, Michelle Saahene and Melissa DePino were in the Philadelphia Starbucks the day when two black men were arrested while waiting for their friend. Soledad O’Brien sits down with both of them to discuss their initiative, From Privilege to Progress, encouraging people – especially white people – need to speak up.