Lady Gaga stands with sexual assault survivors. (Photo by Kevin Winter/Getty Images)

As Lady Gaga performed a song about sexual assault, the curtain behind her slowly lifted. About 50 people emerged, black figures against a blue screen. They stepped forward, out of the shadows, and onto the Academy Awards stage, facing the Hollywood crowd and millions of viewers.

The casually dressed women and men, who looked like anyone you’d pass on the street, raised their forearms to reveal handwritten messages:

Not your fault.

Not alone.

Survivor.

Rachel McAdams and Kate Winslet, both nominated for one of the evening’s glitziest awards, promptly teared up. Based on the social media response, it appears a good chunk of America did, too.

The nation's problem with sexual assault — on campus, in the community and in the Catholic Church — was an unexpectedly prominent theme at last night’s Oscars, an event not exactly known for tackling heavy topics.

"Spotlight," the true story of the Boston Globe reporters who exposed the Catholic Church’s cover-up of widespread molestations, won Best Picture. Mark Ruffalo, who played journalist Michael Rezendes, said on the red carpet that he hoped more victims would feel empowered to step forward.

Brie Larson snagged Best Actress for her role in "Room," a film about a young woman who is kidnapped, raped and forced to raise her child in captivity. "Mad Max: Fury Road," a movie about enslaved women escaping their rapist, swept the audio and visual awards. Vice President Biden delivered a surprise speech saying that sexual assault is never the victim’s fault and urging people to intervene "in situations when consent has not or cannot be given."

Appearing at the Academy Awards, Vice President Biden spoke about ending sexual assault on college campuses. (Courtesy A.M.P.A.S.)

"Let's change the culture,” he said. “We must change the culture, so that no abused women or man, like the survivors you will see tonight, ever feel they have to ask themselves, 'What did I do?' They did nothing wrong.”

And Lady Gaga sang "Til It Happens to You," the Oscar-nominated song she co-wrote about sexual assault on college campuses for the documentary "The Hunting Ground."

Till it happens to you, you don't know

How I feel

Till it happens to you, you won't know

It won't be real

All the attention amounted to an unprecedented pop culture moment for one of the country’s most underreported crimes. Nearly one in five women has endured rape, according to the latest Justice Department statistics. About 14 percent of reported rapes involve a male victim. But federal researchers estimate that only 32 percent of rapes are reported to the police.

Lady Gaga's moving performance of "Til It Happens to You," at the Academy Awards ended with a group of sexual assault survivors joining her on stage. Actress Brie Larson hugged each survivor as they left the stage. (Twitter/Chris Gardner)

Last year, meanwhile, an Association of American Universities survey of 150,000 students at 27 universities found that, since enrolling in college, 13.5 percent of female college seniors and 2.9 percent of male college seniors had experienced sexual assault, which the authors defined as “non consensual penetration involving physical force or incapacitation."

The show's impact could be more than symbolic. High-profile performances, like those on the Oscars stage, can help weaken the stigma that discourages rape victims from reporting the crimes and can start conversations about how authorities should treat cases of sexual violence.

Interviews with 144 female survivors of sexual assault in one 2011 study found that, those who did not report the crime to police chose to stay silent largely because of the social stigma associated with rape victims. They feared judgment or that authorities would not believe them.

Researchers interviewed 434 rape victims for a 2014 study and found that those who received encouragement to go to the police, rather than hide their pain, were much more likely to report an attack. Other research shows talking openly about a traumatic experience can boost the recovery process. 

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