In 1995 Miller's most famous book, Plain Speaking: An Oral Biography of Harry S Truman, became the focus of an intense controversy. That year Dr. Robert Ferrell, an historian who had published his own biography of Truman, asserted that Miller had fabricated many of the quotes in his book. In 1962, Miller had done a series of filmed interviews with former President Truman; his hope was to sell the interviews to a television network. When no network bought the rights, Miller printed the interviews in 1974 and turned them into the bestselling and influential Plain Speaking. In the book, Truman came across as a salty, colorful, and tart-tongued politician who said many "politically-incorrect" things.