Bill Cosby arrives for a preliminary hearing on sexual assault charges Tuesday at the Montgomery County Courthouse in Norristown, Pa. (Mark Makela/Reuters)

At the new year’s dawn, New York Police Commissioner William J. Bratton made an unprecedented announcement: The city had experienced a sharp increase in reported rapes, driven in part by victims bringing forward years-old assaults. One-fifth of the assaults reported in 2015 happened at least a year prior to the police complaint, dating back as far as 1975.

Bratton called this “the Cosby Effect.”

Data from police departments across the country, using the FBI's latest definition, show the Cosby Effect hasn’t struck only New York. Since the entertainer's highly public downfall, people in America's biggest cities began reporting more rapes, especially rapes from the past.

Last year, the District of Columbia saw an 11 percent increase in reported sexual assaults. The number of delayed reports — attacks that happened prior to the year in which they were reported — jumped from 20 to 28.

Philadelphia saw a 9 percent increase, with delayed reports rising from 110 to 121. Houston’s reported sexual assaults jumped 19 percent, with delayed reports climbing from 76 to 125.

Bill Cosby arrives for a preliminary hearing on sexual assault charges Tuesday at the Montgomery County Courthouse in Norristown, Pa. (Reuters)

Los Angeles logged a 12 percent increase in reported rapes, while Chicago’s count surged 7 percent. New York's sum, meanwhile, grew 6 percent.

The Rape, Abuse and Incest National Network, an advocacy organization for victims of sexual violence, also saw a 10 percent increase of calls to its hotline last year.

A cultural shift

The amount of sexual assaults reported in each city likely doesn’t reflect how many rapes actually happen there. An estimated 32 percent of rapes leads to a police report, according to figures from the Department of Justice, and a mere 2 percent lead to a conviction.

That’s why the recent reporting surge is a good thing, said Carol Tracy, executive director of the Women’s Law Project, a Philadelphia advocacy organization that leads research on police response to sex crimes. Higher numbers mean more victims feel empowered to speak up, and more authorities are listening.

But the furor around Cosby, who has been accused of sexual assault by more than 50 women and is due back in court Tuesday, didn’t alone spark the trend.

What Bratton dubbed the Cosby Effect has little to do with Cosby and more to do with the country's evolving understanding of rape.

Over the past five years, Tracy said, the growing pressure to take victims seriously — rather than blame them or question their motives  — has altered the way law enforcement handles rape investigations. Officers, for instance, are more receptive to delayed reports nowadays.

“These are the kinds of cases that, if you tried to take one to many jurisdictions years ago, they just wouldn't take it,” Tracy said. “They just wouldn't count it in their numbers.”

The cultural shift, she theorizes, stemmed from years of grass-roots work in communities by rape crisis centers and a raft of cases that caught the public’s eye and triggered police criticism.

Take the case of Anthony Sowell, a serial rapist who killed 11 women in Cleveland, before his arrest in 2009. Outrage erupted when the public learned that, after a woman reported Sowell choking and raping her, officers took 37 days to visit Sowell’s house, where the bodies were buried.

Delayed reports rise

After several of Cosby’s accusers described assaults that unfolded in the city, New York police started collecting the years associated with each rape, releasing the first round of data in January.

A victim in Queens, for instance, reported an assault from 1975. Another in Brooklyn told police about a 1999 rape. Another in Manhattan described an attack from 2003.

“Some of the rapes [Bill Cosby] is accused of go back 30 or 40 years,” Bratton said on a popular New York City radio show. “We have really made a concerted effort to try and encourage the victims of rape to come forward.”

Los Angeles Police Chief Charlie Beck also spoke publicly about the Cosby accusations, promising the department would investigate any related complaint, no matter how old. “You come to us, especially with a sexual allegation, we will work with you," Beck said in 2014. "We address these things seriously, and it's not just because it's Mr. Cosby."

Removing barriers

Sgt. Elizabeth Donegan, a 23-year member of the Austin Police Department, said police officers in Texas and other states are working to internalize the idea that trauma can impact a victim’s ability to recall information. Someone who’s trying to explain what happened during a sexual assault may appear to be lying, she said, and officers may instinctively slip into interrogation mode.

The APD also stopped asking sexual assault victims to sign forms declaring they wouldn’t commit perjury — a step that could make an already traumatized person feel under investigation.

“Removing barriers like sworn statements was big,” Donegan said. “But I need to be clear — law enforcement still has a long way to go.”

In January, U.S. Attorney General Loretta Lynch called for a sustained effort to fix the way authorities handle rape investigations, releasing new Justice Department guidelines that urged officers to address their misconceptions.

“Acting on stereotypes about why women … are sexually assaulted, or about how a victim of domestic violence or sexual assault should look or behave,” the document states, “can constitute unlawful discrimination and profoundly undermine an effective response to these crimes.”

Racing the statute of limitations

Prosecutors in Pennsylvania leveled the first criminal charges against Cosby in December, asserting the comedian drugged and assaulted former Temple University employee Andrea Constand in 2004.

Constand first reported the assault a year after she said it happened — but at the time, prosecutors decided not to press charges. Evidence that emerged over the last year, however, spurred the charge of aggravated indecent assault, a second-degree felony, said First Assistant District Attorney Kevin Steele. Prosecutors narrowly beat the state’s 12-year statute of limitations, which would have expired in January.

The rise in delayed reports has coincided with policy changes nationwide, as lawmakers push to relax or eliminate the statutes of limitations for authorities to prosecute sex crimes. The windows, which vary by state, can block a victim from filing a report and police from receiving crucial leads on serial rapists.

In California, lawmakers are pushing to join states like Virginia and Maryland in completely removing the sex-crime statute of limitations, which currently stands for most rape cases at 10 years. (Protesters gathered on Cosby’s star last year in Hollywood, calling to end the deadline.)

Indiana enacted a policy last year that allows prosecutors to file rape charges after the state’s five-year time limit has expired if new evidence is discovered, and Florida doubled its window from four to eight years. Oregon extended its deadline in January from six to 12 years.

Over the past two years, awareness of America’s rape kit backlogs has also spiked, said Ilse Knecht, a senior adviser at the Joyful Heart Foundation, a national organization dedicated to ending sexual violence.

The federal government estimated in 2014 that 400,000 rape kits, the DNA evidence collected after an assault, sit untested in the United States. Some victims wait years before they can move forward with their cases. Last year, 11 states passed measures to quash their backlogs and 16 more are currently considering action.

“You get increased awareness and increased attention by legislators,” said Knecht, who helps track rape kit backlogs in all 50 states. "It’s the recipe for more attention and reform.”

Making the call

Brittni Jones, 25, a student studying to become a social worker in Kent, Ohio, decided to take her account of a six-year-old rape to police in 2015. She said she wants to become an advocate for victims someday.

“Telling my story,” she said, “might make them feel better about telling theirs.”

In 2009, Jones visited her cousin in a town near Indianapolis. She anticipated long chats and boot shopping at Charlotte Russe with one of her closest confidantes. But one night, she said, a family friend joined them.

This man, Jones remembers, arrived with a bottle of Patron. The trio blasted reggaeton and danced in the living room until her cousin went to bed.

Jones, then 19 and not used to drinking alcohol, recalls feeling drowsy. Her limbs, heavy. She sprawled out the carpet. The family friend, she said, laid next to her. Then on top off her.

She remembers saying “no” and trying to squirm away. She says he forced himself on her, anyway.

Unsure of what to do, she closed her eyes and eventually passed out. Her cousin found her the next morning, crying in the bathroom. “It took me an hour to be able to say anything at all,” Jones said. “She was just shocked, so shocked.”

Shame stopped her from telling anyone else for years, until she landed in therapy, she says. Themes in Hollywood and in the media inspired her to keep talking about it.  

Jones began watching "Law and Order: SVU," a long-running police drama about detectives solving sex crimes. She heard about the college activists working to quash rape on campus. She saw the women bringing accusations against Cosby, again and again, in the news.

“I thought, ‘Wow, this happens to people,’ ” she said. “When it happens to you, you feel like you’re the only one in the world who’s been through it. You’re so ashamed.”

So, she decided to report the incident to the Hendricks County Sheriff’s Office in central Indiana. The law, however, presented an obstacle: Indiana's statute of limitations on rape, without new evidence, is five years. She'd missed the cutoff.

Still, Jones was glad she made the phone call.

“At least it’s out there now,” she said. “What if he did this to other girls and they reported it and my call led to them deciding to charge him?”

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