Accuracy is the lifeline of statistics, and fudging the numbers is unacceptable.

The city of Toyama on the Sea of Japan coast is suspected to have inflated its population by more than 2,000 people in the 2025 national census. The problem came to light in a Ministry of Internal Affairs and Communications investigation. The preliminary figure for the city's population announced by the ministry in May was 402,133 people, but the final figure in September, after the overreporting was corrected, fell to 399,197.

According to the Toyama Municipal Government's estimates, local allocation tax grants for fiscal 2026, which are distributed by the state to local bodies according to population, had been overpaid to the city by about 60 million yen (about $380,000).

Mayor Hirohisa Fujii has, at this point, denied senior municipal officials were involved. But the system for the 2025 census in the city reportedly had about 2,000 enumerators reporting figures that were then double-checked by more than 300 municipal employees. It is hard to believe that a single employee could have manipulated the figures.

The internal affairs ministry filed a criminal complaint against unnamed municipal employees involved in the misconduct on suspicion of violating the Statistics Act, and Toyama Prefectural Police searched the city's offices. It is essential to uncover the motives behind the irregularities. Whether there were systematic instructions will also be a focus of the investigation.

Important statistics are designated as "fundamental," and among them, the population census provides foundational data. It is used not only to calculate local allocation tax grants but also for the demarcation of House of Representatives electoral districts, disaster preparedness and other purposes. If false numbers are mixed in, they could lead the entire country to make mistaken policy decisions.

That is how significant statistics are. The Statistics Act stipulates imprisonment or a fine for producing false numbers.

Similar cases have occurred. In the 2010 census, the deputy mayor of Higashiura, Aichi Prefecture, was convicted of ordering the population to be inflated. The wrongdoing took place as the town was aiming to reach the 50,000 population threshold needed to be given city status. Figures reported by other municipalities must also be reexamined.

The national government is no exception. Misconduct was uncovered in 2018 in the Ministry of Health, Labor and Welfare's Monthly Labor Survey, and in 2021 in the Ministry of Land, Infrastructure, Transport and Tourism's Current Survey of Orders Received for Construction. Both are fundamental statistics used for assessing the economy, calculating Japan's gross domestic product and other purposes. Measures to prevent a recurrence have since been put in place, including strengthening checking functions.

Toyama's Mayor Fujii has indicated that, citing the ongoing investigation, the municipal government will not conduct its own inquiry for the time being. But the city must fulfill its accountability to residents and the people of the rest of Japan. It should not leave everything to investigative authorities, but move forward with its own verification.

The mechanism of the wrongful conduct must be unraveled, and efforts must be made to prevent any recurrence.