Miyako Shirakawa was a 19-year-old college student when she was raped by an older man. She said that when the attack started, her mind went blank and she froze up.

“When I became aware, he was on top of me,” said Shirakawa, 54, now a psychiatrist who treats sexual abuse victims.

That type of response “is a common, instinctive reaction — it’s a form of psychological self-protection,” said Shirakawa, who became pregnant because of the rape, which she didn’t report to police, and had an abortion.

But under the law, not fighting back can make it impossible for prosecutors to prove rape.

Legislators revised the nation’s century-old rape law in 2017 to include harsher penalties and other changes.

The reforms, however, left intact controversial requirements that prosecutors must prove that violence or intimidation was involved or that the victim was “incapable of resistance.”

A recent series of acquittals has revived outrage over that legal standard, which Shirakawa and other critics say places an unfairly high burden on victims, deterring them from coming forward and hurting their chances in court if they do.

They say the law must be revisited to make all nonconsensual sex a crime, without exception, as it is in other developed countries, including the U.K., Germany and Canada.

“Discussing sexual violence from the victim’s viewpoint is a world trend, and it’s time to reform the Japanese legal system, and society that cannot do that,” said Minori Kitahara, an author and activist who is among the organizers of protests against the recent rulings.