Petro Renews Fraud Claims, Demands Forensic Review of Colombian Election Software

President Gustavo Petro took to social media on Sunday, June 7th to renew his claims that Colombia's first-round election was rigged. He demanded a forensic examination of the counting and tabulation software used on May 31st, insisting that irregularities had occurred at more than 5,300 polling stations. In his posts, he called the owners of Thomas Greg & Sons, the firm that manages the electoral software, "scammers" and accused them of manipulating the process—a charge that has become the centerpiece of his dispute with the country's electoral authority.

The Registraduría, Colombia's official electoral body, has repeatedly denied Petro's core allegations. The agency confirmed that 41.4 million Colombians were registered to vote and that the electoral roll was finalized on April 30th, not two months before the election as Petro claimed. The Registraduría also noted that on May 22nd, it provided campaigns with a software application allowing them to verify individual voter registrations, a safeguard it presented as evidence of transparency. When Petro alleged that more than 885,000 voter identification numbers had been altered, the electoral authority flatly rejected the claim, stating that no modifications to electoral software occurred on May 26th—the date Petro cited—and that the timestamp records he referenced actually corresponded to file access for party auditors, not system edits.

Petro's grievance centers partly on what he describes as his campaign's operational weakness during voting day. He acknowledged that his coalition, the Pacto Histórico, had only 25,000 poll observers deployed across 122,000 voting stations—a significant shortfall. He argued that this absence of observers meant his campaign could not file challenges to results at individual polling places, and that unchallenged results are not subject to recount. "The damage is done," he wrote, framing the first round as already lost due to inadequate oversight rather than outright fraud at the ballot box.

Yet Petro also made a more sweeping claim: that the volume of votes recorded at certain polling stations, particularly those in U.S. consulates, was mathematically impossible. He stated that 600,000 votes cast in those locations exceeded his rival Abelardo de la Espriella's margin of victory, and that the concentration of votes in 5,300 stations was so dense that human voters could not have physically cast them in the time available. This assertion—that the numbers themselves prove fraud—stands as his most direct accusation against the electoral system's integrity.

The Registraduría has countered with procedural facts. The agency reported that during the scrutiny phase, only 0.7 percent of the 122,020 polling stations generated complaints or challenges. International observers and domestic election monitors have publicly affirmed the process's transparency. Judges appointed by the Republic verified the voting, campaigns audited the count, and oversight bodies were present throughout. The electoral authority has thus positioned itself as having met every institutional check designed to prevent fraud.

Petro's latest push for a forensic software audit comes as he prepares for a second-round runoff election. In his social media messages, he emphasized that public mobilization and youth engagement would be decisive in choosing his successor, effectively shifting focus from the disputed first round to the campaign ahead. He also shared a video from journalist Gonzalo Guillén alleging controversial conduct by Thomas Greg & Sons in Mexico, using that example to buttress his call for judicial intervention in Colombia's electoral system.

The dispute reflects a fundamental institutional tension: Petro, as sitting president, is making claims that contradict the formal validation of an election process overseen by courts, audited by competing campaigns, and monitored by international observers. The Registraduría has methodically addressed each of his specific allegations—the census closure date, the software modifications, the observer shortfall—with documentary evidence. Yet Petro continues to assert that fraud occurred, framing his campaign's lack of poll watchers not as a strategic mistake but as evidence of a system designed to prevent oversight. The second round will take place against this backdrop of unresolved institutional distrust.