b) Annulment of the election 544. In order to safeguard the legality of electoral actions and procedures, electoral legal frameworks establish various grounds for the annulment of an election. It should be noted that in electoral matters, as in any other field of public law, not every violation of an electoral legal provision has the same effect. In order to determine the degree of impact it is necessary to look at the legal consequences of the irregular actions or wrongful conduct. 545. Several electoral legal frameworks explicitly provide that annulment may only be decreed on grounds expressly set out in law, although some EDR systems grant the EDRB some discretion within the legal framework to declare the annulment of an election, for example, so long as the ‘facts, defects, or irregularities … influence the general results of the election’ (Uruguay). 546. In general, as an EDR principle, an annulment may only be declared when the irregularity affects the outcome of the election or causes clear bias. In addition, the filing of a challenge does not suspend the effects (even if they are provisional) of the decision or action challenged. Once the period provided for has lapsed without any challenge being filed, the corresponding action or decision becomes final. Also, in the event of doubt (as in Ecuador) or if the two electoral judges differ (as in the UK), the elections are judged valid. The reason for these provisions lies in the general principle in law which states that public actions validly carried out should be conserved. This is reflected in the aphorism ‘the useful should not be vitiated by the useless’, which has special relevance in electoral law, as several EDRBs have noted in their case law (for example Costa Rica, Mexico and Spain). 547. Often, the nullification of an election can only be declared by a judicial EDRB. On occasion, however, it results from an administrative challenge before an EMB (as in Azerbaijan, Croatia, Estonia, Hungary, Kyrgyzstan, Lithuania and Turkey) or a legislative challenge before a legislative EDRB (as in the Netherlands). The rule in judicial EDR systems is that EDRB decisions should be restricted to the issues raised and alleged, and must not address nullities other than those raised in a challenge or complaint. Moreover, based on the provisions of the legislation, annulment cannot be invoked by the person who has caused it, in keeping with another general principle of law that establishes that ‘no one can allege the acts of his/her wrongful intent or clumsiness to his/her own benefit’. 548. Depending on the electoral legal framework, three grounds for the annulment of an election can be identified: (a) as a result of the annulment of the vote at various polling stations; (b) due to the ineligibility of a candidate or slate of candidates; and (c) when the election was not accompanied by the necessary guarantees. 178