The paper analyses the legal consequences of the refusal of the President of the Republic of Poland to sign three acts amending the Act of 6 January 2005 on National and Ethnic Minorities and on the Regional Language, whose purpose was to expand the catalogue of regional languages to include Silesian and Vilamovian. This paper examines this decision from the perspective of the rights of users of the Silesian and Vilamovian languages in the light of the case law of the European Court of Human Rights (ECtHR) concerning language rights. As a result of the veto, users of these languages did not obtain specific guarantees regarding the use of these languages in the public sphere provided for in the 2005 Act. However, an analysis of the ECtHR’s case law indicates that states enjoy a wide margin of appreciation in shaping language policy concerning the official use of languages, since this issue constitutes a regulatory area in which national particularities are especially pronounced and no common European standard exists.