To remain silent is a fundamental right and, as a logical consortary, so too is not to be obliged to declare your guilt even if you have to testify against yourself. It will be verified, therefore, if the interrogated person has a subjective public right to lie or if, by falsifying the information provided, he would be extrapolating his constitutional right of self-defense. For this, the dialectical approach methodology and bibliographic and jurisprudential analysis will be used as a research technique. The problem faced is eminently correlated in the expression, externalization, of language. It is inferred that a person does not have the right to lie before the judicial or police authority, as she will be subject to sanctions typified as crimes (false identity, slanderous denunciation or false self-accusation, verbi gratia).