A Harvard University professor is facing immense scruitiny after alleging that Korean women who were forced into sexual slavery by the Japanese military had chosen to work as prostitutes.

In an academic paper titled “Contracting for sex in the Pacific War,” Japanese legal studies professor J Mark Ramseyer rejected extensive research that found 200,000 “comfort women” were forced to work in military brothels during World War II. Ramseyer claims the women, who were mainly Korean but also Chinese, south-east Asian, Japanese and Europeans, instead entered into contacts as sex workers. 

The belief that the women were not coerced is one that’s shared by conservative leaders in Japan, while South Korea has pushed Japan to compensate women who say they were abused. 

The March issue of the International Review of Law and Economics was set to feature the article, which was initially published online in December, but has since been suspended it. The piece is now under investigation, according to the journal.

Since the academic paper went live in December, scholars around the world have signed letters condemning it. Last week, North Korea’s DPRK Today published an article calling Ramseyer a “pseudo scholar.” In Japan, historians issued a 30-page article saying Ramseyer’s article should be retracted “on grounds of academic misconduct.”

Over 1,000 economists have also signed a letter condemning the article, as they claim it twists economic theory “as a cover to legitimize horrific atrocities.” Even at Harvard, hundreds of students are demanding an apology via a petition.

Several historians have said there’s a lack of evidence in the paper, as Harvard historians Andrew Gordon and Carter Eckert called for it to be retracted.

“We do not see how Ramseyer can make credible claims, in extremely emphatic wording, about contracts he has not read,” they said in a statement.