UPDATE 3-Mexico scraps tainted GM union vote, cites 'irregularities'
Recasts with Mexico labor ministry on vote
By Daina Beth Solomon and David Shepardson
MEXICO CITY, May 11 (Reuters) - Mexico's labor ministry on Tuesday said it found "serious irregularities" in a union-led vote at the General Motors Co plant in the city of Silao, and ordered the automaker's union to re-hold a vote within 30 days.
The Mexican ministry's move followed pressure earlier in the day by U.S. lawmakers on GM GM.N to ensure worker rights at the Silao plant, adding to concerns from global labor advocacy groups.
Mexican officials had previously said that some ballots were destroyed during the vote in April, which was intended for workers to ratify their collective contract.
The ratification is required under a Mexican labor reform to ensure workers are not bound to so-called protection contracts, which are signed behind workers' backs and prioritize company interests.
Such votes are part of the broader effort underpinning promises in the United States-Mexico-Canada Agreement (USMCA) free trade pact to uphold worker rights. nL1N2MX1UN
The ministry said in Tuesday's statement that the GM vote had "violated principles of safety and certainty that should govern every democratic process."
GM has denied wrongdoing and said it condemned labor rights violations.
(Reporting by Daina Beth Solomon in Mexico City
Additional reporting by Sharay Angulo and Anthony Esposito in Mexico City, Ben Klayman in Detroit and David Shepardson in Washington
Editing by Christian Plumb, Matthew Lewis and Grant McCool)