With the end of the monarchy, the power of the people went from being in the hands of the bourgeoisie to being the legitimate property of society, although in a conditioned way (Bernays, 1928, p. 19; Castillo, 1989). Ever since then it has been the object of an attempt of manipulation, by sectors of political interest in search of its particular benefit. Subliminal publicity is present as a possible element within these activities, in the assumption of manipulating the citizen’s opinion even against his will. This paper presents an investigation carried out by an experiment with 326 people, to verify their efficiency or inefficiency under a strict methodological-scientific follow-up, with which it has been verified that manipulation is not possible, but the evidence indicates that it could confuse the opinion of the citizen.