Abstract
This article examines a specific case of lying, at the same time judicial and mediatic, promoted from the highest levels of political power, the Leon Trotsky case, from the perspective of the work done by the International Commission of Investigation chaired by the American philosopher John Dewey. After a general justification and contextualization of the subject, and a historical account of the events that surrounded the “Moscow Trials” and the constitution of the Dewey Commission, some of the reasons why the commission concluded that such processes had been judicial assemblies are reported. It closes with a reference to the way Dewey later denounced the media falsification of these events through the book Mission to Moscow.