Political wrangling over an envisioned shake-up of the immigration control law has intensified in recent days after the government admitted last week to multiple statistical errors concerning the state-sponsored foreign trainee program.

The government wants to pass the legislation by the end of the ongoing Diet session, which is slated to wrap up Dec. 10. The intended revision marks a drastic break with previous policy in immigration-shy Japan, paving the way for an influx of blue-collar foreign workers in some of the most labor-hungry industries for what could become an indefinite period of time.

An opposition backlash to the amendment, however, has flared anew over the lapses in preparing statistics, which came to light Friday, leading to a stalemate among lawmakers in the Diet that could derail the government’s intended timeline for passing the amendment.

But even so, the ruling bloc could theoretically resort to extending the legislative session to ensure the bill clears the current Diet session — a prerequisite for the new visa system to come into effect in April next year as has been hoped by the government.

The Justice Ministry admitted Friday to data inaccuracies in its 2017 probe into foreign trainees who went missing from their workplaces, and issued a number of corrections at an informal gathering of Lower House judiciary committee members.

The data errors immediately prompted the Constitutional Democratic Party of Japan to submit a resolution seeking to remove Liberal Democratic Party lawmaker Yasuhiro Hanashi from his position as head of a Lower House judicial affairs committee, which is tasked with discussing the immigration law. A resolution against Hanashi is expected to be voted down by the ruling coalition in Tuesday’s plenary session, but has succeeded in pushing back deliberations on the amendment by a few days.

The inaccuracies in the data included describing those who had decided to leave their workplace because of low wages as having gone missing because they “sought jobs with higher wages.”

As a result, the ministry’s original data overstated the number of interns reported to have said their motive for leaving was to seek better pay, rather than to escape from rock-bottom wages or workplace violence. The government had argued that the reason so many foreign trainees exit the program is because they wanted better opportunities with higher wages.

On Friday, the ministry revised the number who had gone missing to seek “better job opportunities” from the original 2,514 down to 1,929.

On the other hand, the number of people reported to have claimed they had left because they had been disciplined harshly by their superiors more than doubled, with the figure rising from 155 to 362 people. The number of people who claimed they had been subjected to physical abuse also jumped, from 88 to 142.

On an NHK program on Sunday, CDP lawmaker Akira Nagatsuma said the faulty data paints an inaccurate picture of what is formally called the Technical Intern Training Program, obfuscating the reality of abuse and exploitation that critics often say underlies the program.

“The original data on the missing interns made it look like they escaped in pursuit of higher wages, when in fact that’s not entirely true. Many were desperate to get away because they faced violence or were forced to work for wages lower than the minimum level,” Nagatsuma said.

The Justice Ministry attributed the errors to the mishandling of an Excel spreadsheet. But a closer look into the multiple-choice survey also reveals that the ministry lumped together responses such as “wage is low,” “actual wage is lower than contracted wage,” and “actual wage is below the minimum level” into one and presented it, simply, as “seeking higher wages.”

Separately, the number of those who deserted employers because they wanted to continue working after their enrolment in the foreign trainee program expired also rose from 392 to 510.

Moreover, the report, which surveyed in 2017 a total of 2,870 trainees who went missing from their workplaces that year, showed that 2,664 individuals — or about 90 percent of the trainees surveyed — received a monthly wage below ¥150,000.

Speaking on the same NHK program, lawmakers from the LDP-Komeito ruling bloc admitted that the errors were problematic.

Still, Norihisa Tamura of the LDP defended the envisioned new visa system, saying it would replace the trainee program as an official source of foreign labor and go a long way toward making it function in a more conventional manner.

“The thing about the foreign trainee program is that employers sometimes operate under the misguided notion that they don’t need to give the trainees minimum wages because they are not official workers, but just interns,” Tamura said.

“Under the new system, the interns can transition to gain official employment status, which would help them secure their rights as laborers … Once the new system takes hold, the trainee program will then specialize in its original purpose” of fostering foreign talent who can learn and take Japan’s industrial expertise back to their home countries.

Nagatsuma, however, said that the government’s effort to pass the bill by the end of the current Diet session — in the absence of proper budgetary measures or thorough soul-searching about the existing problems under the trainee program — will only lead to further problems, and insisted that debates on the law should be carried over until next year.

He went on to suggest that the government’s lack of preparation echoed miscalculated immigration policies seen in Germany and France in the mid-20th century that led to those known as guest-workers being alienated from mainstream society.

“Those foreign workers are human — not some object you can accept and then throw away once their demand has fizzled out. We need to have a serious think about this in the Diet,” Nagatsuma said.