"Errors in litigation are actions of the court, parties and other participants in the litigation that are contrary to procedural law, i.e. the provisions governing the conduct of civil proceedings. Substantial errors are those actions and procedures that lead to irregularities in the litigation, illegal judgments and also damage protected goods. Only on the occasion of such errors can legal remedies be successfully filed against the judgments and decisions of the courts. Substantial errors are divided by law into absolutely substantial and relatively substantial. A division is made between errors depending on how hard their existence affects procedural law. An absolute error is the existence of a serious failure in the conduct of the litigation, which includes the judgment that was passed and all procedural actions covered by such an error. The decision is absolutely null and void and should be revoked. The law in Art 354, paragraph 2, specifies when there are always substantial errors in the litigation. Relatively substantial errors are difficult to define in this sense, because they are "activated" only when an error that is not on the list of absolutely substantial errors causes an illegal and irregular judgment. Therefore, it is necessary to prove a cause-and-effect relationship between what we consider an error and the legality or the regularity of the verdict."