The legal foundations and the individual votes of the first sentence show that in weighing the limits on the freedom of expression of politicians, the fact that the demonstrations have been broadcast in an electoral campaign must be taken into account and also the relationship between the content of the demonstrations and the political program of his party. In the second case analyzed, the circumstances that shape the limits to the freedom of expression of a politician are valued for the real harm of the minority that feels injured by the political declarations as well as for the seriousness of the sanction imposed on the politician. The two judgments of the ECHR that we have tried to compare reveal the difficulty of constructing general criteria in the interpretation of the freedom of expression of political representatives. The elaboration of too abstract general criteria, may not guarantee that the abusive and unlawful exercise of this right is prevented. There is not yet enough jurisprudence to elaborate a solid dogmatic construction on the abuse of rights in the exercise of freedom of expression. Likewise, it is convenient to be aware of the advantages and the risks that the conventional legal concepts that already have a stable interpretation entail. Summary:1. Introduction. 2. Summary exposition of both sentences. 2.1. Féret c. Belgium. 2.1.1. Summary of events. 2.1.2. Summary of decision. 2.1.3.Final thoughts. 2.2. Perinçek c. Switzerland. 2.2.1. Summary of events. 2.2.2. Summary of decision. 2.2.3. Final thoughts. 3. Interpretative criteria of the limits to the freedom of expression of politicians. 3.1. Freedom of expression of the political class. 3.2. Interpretative criteria of some indeterminate legal concepts of conventional law. 3.3. Restrictive application of art. 17 of the ECHR. 4. Conclusive considerations.5. Bibliographic references. ; Los fundamentos jurídicos y los votos particulares de la primera sentencia ponen de manifiesto que, en la ponderación de los límites a la libertad de expresión ...