The principle of informing parties in the Polish administrative procedure is specified in Article 9 of the Act of 14 June 1960, the Code of Administrative Procedure. Public administration bodies are obliged to duly and comprehensively inform the parties on the factual and legal circumstances that may affect the determination of their rights and obligations being the subject of administrative proceedings. The authorities ensure that the parties and other persons involved in the proceedings do not suffer damage due to ignorance of the law, and for this purpose they provide them with necessary explanations and instructions. In administrative proceedings, not the principle of ignorantia iuris nocet the obligation of the authority, resulting in particular from Articel 9 CAP is to inform the party about the factual and legal circumstances that may affect the determination of rights and obligations that are subject to current or potential behavior. This principle applies in particular to proceedings in the field of social assistance and proceedings in the field of family benefits, where a specific law is shaped in accordance with the activities of the party. It should be assumed that a breach the party‘s information rules is an intrinsic and sufficient reason for repealing the decision, even if it is in accordance with substantive law.