In democratic legal systems there is a wide variety of instruments which profoundly affect the composition of future parliaments. They can cause significant changes in final results of both the parliamentary and municipal election. Due to them political parties can improve their position in emerging legislatures (gmina councils, poviat councils or sejmiks of the voivodeship), or even, I mean smaller formations in the first place, can guarantee any representatives in the chamber (council, sejmik). Politicians make use of these instruments most frequently in the face of the oncoming election. These mechanisms allow, on the grounds of binding law, to cause a result much worse than expected for the opposition or formations competing for power. In countries with deeply rooted democracy, it is most often a good political habit that makes any changes in the Electoral law take place long from the election. In our political reality, however, it is a rule that the election campaign is accompanied by auctions on legal grounds. Namely, changes in the borders of election districts take place, vote calculation methods are modernised so that they would be naturally beneficial for those who carry out such normative transformations.