 An aide to Senator Kerry at the time said “Quite frankly I don’t think our investigation would have proceeded without John”.As a Federal Defender in Miami, Mattes found himself in the thick of the cloak-and-dagger incidents of the Contras and their allies.Mattes defended self-described mercenary whistleblower and freelance intelligence operative Jack Terrell from charges he had violated the U.S. Neutrality Act because of his Contra-supply work.