Japan’s government has issued an apology and awarded compensation to thousands of people with disabilities who were forcibly sterilised under a now defunct eugenics law.

As part of legislation that passed parliament’s upper house on Wednesday, surviving victims will each receive ¥3.2m (£22,000) to compensate for their suffering, as well as an apology from the state “for the great physical and mental suffering caused by the forced sterilisation programme”.

The prime minister, Shinzō Abe, voiced “sincere regret” and said the government “apologised wholeheartedly” for the policy, under which people as young as nine were sterilised against their will.

“During the period the law was in effect, many people were subjected to operations that made them unable to have children based on their having a disability or another chronic illness, causing them great suffering,” he said in a statement.

“As the government that carried out this law, after deep reflection, I would like to apologise from the bottom of my heart.

“We will do all we can to achieve a society where no one is discriminated against, whether they have illnesses or disabilities, and live together while respecting each other’s personality and individuality.”

About 16,500 people, mostly women with disabilities, were targeted between 1948 and 1996 under a law that aimed to “prevent the birth of poor-quality descendants”. About 8,000 other people gave their consent – most likely under pressure – while almost 60,000 women had abortions because of hereditary illnesses, according to media reports.

The compensation will be paid to all survivors who were sterilised, including those who reportedly agreed to undergo surgery, according to the Kyodo news agency.

People with mental disabilities and illnesses, along with those with hereditary disorders, were made to undergo the procedure “to prevent the birth of inferior descendants … and to protect life and health of mother,” according to the eugenics law.

Germany and Sweden had similar measures, but have since apologised to victims and provided compensation.

Japan’s government had until recently maintained that the sterilisations were legal at the time.

But calls for redress grew last year when victims launched lawsuits seeking compensation of about ¥30m each from the government.

They included a woman who was 15 when she was sterilised in 1972 after being diagnosed with a mental disability. Official records suggested she was sterilised because of “hereditary feeble-mindedness” – a diagnosis that was disputed by her family.

About 20 victims are separately suing for larger sums, and a court in Miyagi prefecture in the north-east of the country is expected to issue the first ruling in these cases late next month.

The plaintiffs’ lawyers claimed the one-off compensation offered by the government was insufficient. “It is understandable that lawmakers have been hurrying to enact the law to pay one-off compensation to ageing victims,” they said in a statement before the law was passed on Wednesday.

But without sufficient compensation, it was not a “satisfactory solution to the issue”, the lawyers added.

One of the plaintiffs from Miyagi, a woman in her 70s, said: “The government hasn’t dealt with it properly for the past 20 years, and that makes me angry. I want the prime minister to apologise to me to my face.”

The campaign for redress has highlighted the Japanese state’s mistreatment of people with disabilities and chronic conditions in the period after the second world war.

It rounded up thousands of leprosy patients and forced them to live in sanatoriums located in mountains or on remote islands. Many were sterilised or made to have abortions. The segregation law was not repealed until 1996.

In 2001, a court ruled the policy of segregating people with leprosy was unconstitutional and should have been discontinued after effective multi-drug therapies were made widely available by the end of the 1950s.

The then prime minister, Junichiro Koizumi, issued a formal apology and said the state would not fight compensation claims brought by former patients.

Justin McCurry

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