Raúl Carrancá y Trujillo was a Mexican judge who experimented with ways of integrating psychoanalysis and criminology. He corresponded with Freud and Freud applauded his efforts. In 1940 Carrancá was assigned the case of Ramón Mercader, who was accused of assassinating León Trotsky, and he deployed his psycho-judicial techniques to investigate the unconscious motives behind the killing.