Penal majority is the subject of 43 Proposals to amend the Constitution that aim to change current
legislation. In order to identify the most frequent arguments present in these Proposals, their justification texts were analyzed by two different methods. In Study 1, these arguments were grouped into categories, which were submitted to an inter-judges concordance analyses. In Study 2, the justification texts were submitted to a Lexicographic Analyses using the software IRAMUTEQ. In booth studies, the most frequent arguments were: age as the only criterion to assume imputability is insufficient; the current legal order and comparative law studies provide evidence that adolescents should be held criminally responsible; changes in legislation are necessary to reduce criminality. Logical and conceptual errors, together with a lack of empirical evidences, in the Proposals’ texts, may lead to inaccurate conclusions and, consequently, to decisions that conduct to undesirable results.