[2][3] The Organization of American States (OAS) conducted an audit claiming "clear manipulation" and significant irregularities,[4] releasing a full report afterwards.

[8][9] The New York Times later concluded on the basis of a new study by independent researchers and academics that the initial report was flawed as it was released too early, relied on poor datasets and used inappropriate statistical methods.

The study found that there was no statistical evidence of voter fraud as the audit had claimed; OAS stood by their report but refused to disclose the full methodology and dataset.

[2] Hours later he and his vice president Álvaro García Linera were forced to resign from office after losing support from the police, the Bolivian Workers' Center and the military.

[23] She also stated that they had been given an "information seminar" about all the logistic, legal and communications issues related to the primary and had even visited polling stations to make assessments and recommendations.

The first one, Transmisión de Resultados Electorales Preliminares (TREP), is a quick count process based on photographs that is meant to provide a preliminary result on election day.

[59][60] Bolivia's Supreme Electoral Tribunal (TSE), stated that updates to the preliminary count had been halted because the official results were starting to be released.

Protesters and opposition politicians called for a second round to be held despite Morales' lead, as did the governments of Brazil, Argentina, Colombia, the United States, and the European Union.

[75] On 6 November, the opposition published a report stating there had been electoral fraud, including cases where MAS allegedly obtained more votes than the number of registered voters.

[76] On 10 November, the Organization of American States Electoral Observation Mission in Bolivia published a preliminary report of the audit conducted during the elections.

[78][79] By late afternoon of that day,[80] Morales and his vice president, Álvaro García Linera, resigned from office after losing support from the police, the military, and former political allies.

[81] On 5 November, Professor Walter R. Mebane at the University of Michigan used his own "eforensics" model to detect and predict the level of fraud that occurred during the election.

[84] In their official report, one source for the OAS, they stated "We cannot attest to the integrity of the electoral results because the entire process is null and void due to the number of alterations to the TREP source code, the number of accesses and manual modifications with the maximum privileges to the databases being created during the electoral process and the inconsistencies in the software that arose in the TREP and Computo.

[59] The CEPR report said the OAS "provided no evidence to support these statements suggesting that the quick count could be wrong" and postulated that the irregularities they perceived were instead merely the result of normal geographic voting patterns, noting that "later-reporting areas are often politically and demographically different from earlier ones".

[53] The CEPR report argued that due to Morales' voter base being in more rural regions, the later-arriving results from peripheral areas were more likely to be in his favor.

The findings included that an outside user who controlled a Linux AMI appliance with "root privileges" — conferring the ability to alter results — accessed the official vote-counting server during the counting and that in a sample of 4,692 returns from polling stations around the country, 226 showed multiple signatures by the same person for different voting booths, a violation of electoral law.

All in all, the OAS's statistical analysis and conclusions would appear deeply flawed" and that "it is highly likely that Morales surpassed the 10-percentage-point margin in the first round" as originally presented.

[94] The OAS reiterated their criticisms of the original CEPR report and issued a statement to say that "the mentioned article contains multiple falsehoods, inaccuracies and omissions.

[97] On 10 March 2020, Irfan Nooruddin, Professor in the School of Foreign Service at Georgetown University and author of Elections in Hard Times: Building Stronger Democracies in the 21st Century, wrote a Washington Post article to defend the analysis he performed as the head of the OAS statistical study included in their audit.

[100] On 12 March 2020, Professor Rodrigo Salazar Elena, researcher at the Latin American Faculty of Social Sciences in Mexico, wrote an article in Voz y Voto magazine in which he compares and discusses the claims and evidence shown in the OAS and two CEPR studies.

He states that in order to rebut the OAS analysis and account for the increase in Morales's vote share, it would be necessary to identify a feature distinguishing voters on either side of the threshold.

[102] Reached for comment by the New York Times, Irfan Nooruddin, who conducted the OAS's statistical analysis, said that Rodríguez and colleagues' study was wrong and did not accurately represent his work.

[101] In August 2020, after Nooruddin published the dataset he used for his audit to a Harvard University digital repository,[106] CEPR reported that they had found a "fatal flaw" in the data which "negat(ed) the OAS's claims that fraud affected the results".

The investigation also alleged that a number of foreign individuals, some linked to Mexico's Labor Party, an ally of the governing National Regeneration Movement, were involved in the meeting .

[111][112] The same month, the Bolivian prosecutors office also released a report corroborating 16 pieces of evidence indicating willful manipulation of the election results.

This included redirection of server traffic to a network outside the control of the TSE, falsified tally sheets, burned voter index lists, poor chain of custody not guaranteeing that the material had not been tampered with and modification of data from a number of polling stations.

[113] In December 2020, CEPR released another response to the concerns raised by the OAS, writing that "when within-locality variation is taken into account, the election results stand up to scrutiny".

[116] On 23 July 2020, the TSE announced that the election would be postponed to 18 October 2020, due to medical reports that the pandemic would have its highest peaks in late August and early September.

[117][118] The 2020 Bolivian general election was indeed held on that date, resulting in a first-round win by MAS candidate Luis Arce, former minister of economy and public finance and ally of Evo Morales.