Court rules barcode and QR-coded ballots constitutional

Thailand’s Constitutional Court ruled on Monday (September 28, 2026) that the use of barcodes and QR codes on ballot papers in the February 8 general election did not violate the Constitution or undermine the principle of secret voting, leaving the election intact under this challenge.

The court delivered its ruling at 2pm in case No. Tor 30/2026, brought by the Office of the Ombudsman under Article 213 of the Constitution after receiving 22 complaints over the Election Commission’s (EC) ballot design.

The complaints argued that barcodes and QR codes printed on ballots could potentially be used to trace individual voters and their choices, raising questions over whether voting remained genuinely secret and whether the system infringed constitutional rights.

Court says codes serve election-management purposes

The court found that barcodes were introduced to prevent counterfeit ballots, control ballot numbers, prevent ballots from being used outside their designated constituencies and improve the printing and distribution process within the limited time available before an election.

It said the measure supported the administration of a free and fair election and allowed individual ballot papers to be monitored through the printing and allocation process.

Although other anti-fraud methods such as watermarks or special markings could also be used, the existence of alternatives did not in itself make the barcode system disproportionate, the court found.

Barcode alone does not reveal how a voter voted

The court said a barcode printed on a ballot does not directly show which candidate or party a voter selected.

Identifying an individual voter’s choice would require additional information and a process linking three separate sets of records — the ballot paper, its counterfoil and the electoral roll. Access to those materials is subject to security and document-control procedures.

The court found insufficient evidence that any person or agency had combined those records to identify how a complainant or other voter had cast their ballot.

It therefore ruled that the use of barcodes and QR codes had not destroyed the essential principle of ballot secrecy or violated voters’ rights and freedoms under Articles 50(7), 83 paragraph two and 85 paragraph one of the Constitution.

Court raises concern over public confidence

Despite finding the system constitutional, the court noted that the controversy had affected public confidence in the election process.

It said future ballot designs should take account of both anti-counterfeiting requirements and the need to avoid markings or symbols capable of being linked to information identifying individual voters.

The court also called for particularly strict safeguards governing the storage and control of the ballots involved in the case to prevent unlawful access to information that could potentially be used to trace votes.

EC officials attend ruling

Election Commission chairman Narong Klanwarin attended the hearing, along with Pol Capt Chanin Noilek, deputy secretary-general of the EC, representatives of the Office of the Ombudsman and one of the complainants. EC secretary-general Sawaeng Boonmee also attended the court proceedings.

When reporters asked Narong before the ruling whether his attendance reflected confidence in the outcome, he replied briefly that the court had prohibited him from commenting.

The Constitutional Court proceeded with the scheduled ruling despite the government declaring September 28–29 holidays for government agencies in several flood-affected areas, saying a postponement would disrupt its timetable for other cases already scheduled through October.