International Foundation for Electoral Systems which led some stakeholders to call for the annulment of the result and a revote.56 However, it seems unlikely that these violations would support the annulment of results under the test set out in Morgan v. Simpson (discussed above). In Turkey, a 2017 constitutional referendum led to the adoption of a set of amendments to the Constitution that expanded the powers of the president.57 Those in opposition to the referendum, along with international observers, claimed that a significant number of unstamped ballots were counted, which was contradictory to the law and possibly the result of fraud.58 International observers noted that the vote had been carried out in a political environment in which fundamental rights and freedoms had been curtailed, as Turkey has technically been in a state of emergency since the coup attempt the previous year.59 The main opposition party lodged an appeal with the European Court of Human Rights (ECtHR) seeking to annul the results of the petition, after appealing unsuccessfully to the Constitutional Court of Turkey.60 However, the ECtHR ruled that the petition was inadmissible as the provisions on “free elections” in the European Charter could not be interpreted as extending to referendums.61 However, as we state above, referendums are often exposed to the same integrity vulnerabilities as general elections, and the annulment remedy should be available for referendums on the same grounds as other elections. IV. Procedural Considerations Given the high stakes in annulment cases and the risks of ill-conceived or bad-faith annulment decisions, it is critically important that the procedures governing such cases be well-designed and established well in advance of the start of an electoral process. Key procedural considerations include: who has the burden of proof, the standard of evidence that will be applied, and the timelines that govern the process. Presumption of Validity and Burden of Proof The existence of unsubstantiated challenges to election results represents a challenge to the legitimacy of elected officials and the credibility of elections themselves. For that reason, official election results 56 Laura Kuenssberg, “Vote Leave broke electoral law, Electoral Commission expected to say,” BBC News, July 4, 2018, https://www.bbc.com/news/uk-politics-44704561. 57 Kareem Shaheen, “Turkish election board rejects call to annul referendum result,” The Guardian, April 19, 2017, https://www.theguardian.com/world/2017/apr/19/turkish-election-board-recep-tayyip-erdogan-referendum; Commission on Security and Cooperation in Europe, Highlights of Conclusions and Recommendations Drawn from OSCE Election Reports: October 2016 to September 2017, 14-15, https://www.csce.gov/sites/helsinkicommission.house.gov/files/Addendum%20to%20Report%20%20Democratic%20Elections.pdf. 58 OSCE/ODIHR, “Republic of Turkey Constitutional Referendum, 16 April 2017: Limited Referendum Observation Mission Final Report,” June 22, 2017, https://www.osce.org/odihr/elections/turkey/324806. 59 Office of the United Nations High Commissioner for Human Rights, Report on the Impact of the State of Emergency on Human Rights in Turkey, March 2018, https://www.ohchr.org/Documents/Countries/TR/2018-0319_Second_OHCHR_Turkey_Report.pdf. 60 “Turkey Opposition Appeals Erdogan’s Referendum in EU Court,” Deutsche Welle, July 4, 2018, https://www.dw.com/en/turkey-opposition-appeals-erdogans-referendum-win-in-eu-court/a-39536871. 61 Cumhuriyet Halk Partisi v. Turkey (application no. 48818/17). 16