Well, many of us who have worked in the government or who work with the government, when I represent secret service officers and the military, also have access to secret information. I sign a confidentiality agreement. It concerns only classified information. I can say anything that is not classified. The Trump campaign is suing former aide Omarosa Manigault Newman for allegedly violating a confidentiality agreement she signed when she joined the campaign. The Trump administration has also reportedly tried to get White House staff to sign similar agreements. What is an NDA and how are they used by the federal government? William Brangham receives an analysis from lawyer Mark Zaid. Absolutely.