Appeal bodies should have the authority to annul elections. There is consensus that the annulment should not necessarily affect the entire election. Instead, partial invalidation should be possible if irregularities affect a small area only. The central criterion for (partly or completely) annulling elections is, or should be, the question of whether irregularities may have affected the outcome, i.e. may have affected the allocation of mandates. In some countries, however, the electoral law establishes a tolerance level for fraud (based on certain percentages of irregular votes), a practice which does not meet international standards. Following complaints of election day irregularities, recently, election results have been annulled in some polling stations, inter alia, in Serbia (2017) and Russia (2018). In Austria, the presidential elections of May 2016 were repeated after the constitutional court annulled the election results.