The Constitutional Court plays an important role in countering radicalisation. This article analyses the concept of radicalisation in the context of the Polish Constitution and the jurisprudence of the Polish Constitutional Court. It debates whether Article 13 of the Constitution (prohibition of certain political parties and organisations) offers enough competence for the Constitutional Court to effectively protect democratic values and the rule of law from radicalisation. It suggests that a gradation of sanctions for the violations in the context of radicalisation by political parties and organisations could be introduced.