On their wedding nights, hundreds of men and women, some who had never met until the collective ceremony when they were bound in marriage, held each other in fear as they were forced to consummate their union under the watchful eyes of Khmer Rouge cadre.

Beginning on Tuesday, the Khmer Rouge tribunal will hear the stories of the victims of these forced marriages – or “red weddings” – as they are prosecuted as a crime against humanity.

Academic Maria Elander, whose article Prosecuting the Khmer Rouge Marriages appeared in the Australian Feminist Law Journal earlier this month, wrote the charges “stand as the only alleged crime of sexual and gender-based violence” that the tribunal will hear.

As such, she said, the stakes are high.

While some male soldiers were gifted a spouse of their choice, Elander points out that both men and women were forced to marry without choice or consent, meaning both could be victims of the same rape, and the omnipotent “Angkar” the perpetrator.

Some witnesses have already testified that Khmer Rouge cadres were stationed outside the huts of newlyweds to “monitor” the consummation. Some couples stayed together and raised children; others separated after the regime’s fall.

Elander said when the court began operating 10 years ago, sexual violence was not considered widespread due to strict moral codes against violating women, extramarital sex and rape. But the regime’s regulation of marriage was considered as a potential crime after civil parties came forward on the often-taboo topic.

Civil party lawyer Marie Guiraud said 779 civil parties are admitted to Case 002 as victims of the Khmer Rouge’s regulation of marriage, including siblings or relatives of those forced to wed. Of those, 474 were “direct victims” who were forced to marry.

Watch: Marriage under the Khmer Rouge

According to the closing order of the court, mass ceremonies ranged from two couples to more than 100.

“By allegedly imposing the consummation of forced marriages, the perpetrators committed a physical invasion of a sexual nature against a victim in coercive circumstances in which the consent of the victim was absent,” the closing order reads.

Elander notes, citing the work of academic Peg LeVine, that the crime was not only against individuals, but also ruptured societal bonds and broke with tradition; a kind of “ritualcide” that altered the way Cambodians engaged with spirits and ancestors.

Ultimately, Elander said, it was a “fantasy” that the law could hold the complexity and contradictory experiences of marriage under the regime, but was hopeful it would shed light on the sensitive crime.

Documentation Center of Cambodia director Youk Chhang said the forced marriages were part of a complete “dehumanisation” project by the Khmer Rouge.

“The Khmer Rouge regarded people as elements. They took away our humanity and everything else. They dehumanised us and then they chopped us into pieces,” he said.

“The Khmer Rouge can force you to not even drop a tear when you are sad or scared or when you beg for forgiveness.”

Ros Sopheap, executive director of NGO Gender and Development in Cambodia, said Khmer Rouge marriages were an invasion of private life and a violation of a person’s essential choice about who they love.

“They had no choice, no power . . . if you didn’t like [your spouse], you could not say anything,” she said.

She hoped airing the truth of the victims will prove a vital lesson to the next generation.

“We need to learn not to let this happen again,” she said.