In March 1993, a 40-year-old Cleveland crack addict, later called “Ellen” in local media reports, was viciously attacked and raped. She said her attacker came up to her on the street, hit her with a brick, sprayed her with mace, raped her and tried to strangle her with her sock. Her wounds required 300 stitches. But it wasn’t until 20 years later that police came to her door and announced they had a suspect. Charges were filed one day before the statute of limitations ran out.

Ellen’s case is one of thousands being reopened in a new national push to account for the what has been dubbed a vast “backlog” of untested “rape kits,” biological evidence collected from victims of alleged sexual assaults that has languished for a variety of reasons — some legitimate, others remiss — before it’s compared to a national database of known criminals and unsolved crimes. There are an estimated 400,000 untested kits nationwide. And clearing the backlog has become a cause celebre for politicians, prosecutors and advocacy groups.

Inadequate funding is one explanation for the logjam: each kit can cost up to $1,500 test. Police departments across the country are increasingly turning to state legislatures and federal grants to help pay for testing. The Memphis Police Department last month announced it would seek $500,000 from the state of Tennessee to test 2,226 kits on its shelves. Congress recently approved funding for nationwide audits. And this month, thanks in part to a three-year crusade by pink-sneakered state senator Wendy Davis, Texas will begin spending $11 million in state funds to examine an estimated 20,000 untested kits, according to the Texas Department of Public Safety. It could pay particular dividends in the state, which does not have a statute of limitations on rape cases.

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But the reasons behind the buildup are not entirely understood—the federal government has awarded research grants to Houston and Detroit to explore why so many have sat on shelves for so long. Law enforcement officials say there are some investigations where analyzing a rape kit is deemed unnecessary. And the new wave of testing and prosecutions comes with complications. As Ellen’s case demonstrates, victims, along with accused attackers, may face a traumatic journey into their dark pasts.

The math of the rape kit backlog is not simple. 400,000 untested kits do not equal 400,000 missed rape prosecutions. Only an estimated 50% to 60% of rape kits contain biological material that does not belong to the victim, according to a National Institute of Justice report. And police sometimes forgo rape kit analysis if the suspect was known to the victim or confessed, or when the victim is uncooperative or missing, says Asst. Chief Mike Slinkard, head of forensics for the Houston Police Department.

Nonetheless, testing a backlog of rape kits does lead to more prosecutions. More rape cases went to court in New York City after a cold case task force began sorting through old evidence in 1999. In Ohio, where Cleveland officials began analyzing 4,000 kits in 2009, resulting cases are now hitting the Cuyahoga County courts, where there are 58 rape kit-linked indictments now pending, according to the Cleveland Plain Dealer. Ellen’s case, which was the first to go before a Cuyahoga County jury, ended in late August. It illustrated many of the challenges in prosecuting old sexual assault cases.

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When Ellen’s backlogged rape kit was tested, it led to a hit in the national database identifying 43-year-old Anthony Moore, who was in the system because he had been charged with kidnapping when he ran off with his infant son following a domestic incident with the child’s mother. Moore pled not guilty to the 1993 rape, telling jurors he had been a crack addict who regularly hung out near the crime scene and had numerous sex partners in the neighborhood. His lawyer, Michael O’Shea, did not contest the DNA link, but pointed to a lack of further evidence: no sock, no brick, no crime scene photos. Jurors found Moore not guilty.

Ellen’s case is not necessarily typical. Law enforcement officials say old rape kits can break important cases. In Houston, some 6,663 kits have been identified and moved out for testing, Slinkard says. Based on previous findings, approximately 5%-10% will lead to a hit in the database, which may discover repeat offenders, according to Torie Camp, deputy director of the Texas Association Against Sexual Assault. Some of the Cleveland cases involve unidentified serial rapists. “The patterns are where it is really compelling,” Camp says. In Ohio, 60-year-old Charles Steele, was serving a 25 year term for two 1994 Cincinnati rapes when testing linked him to four 1993 Cleveland area rapes. He was indicted earlier this year and awaits trial on the four new charges.

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As the kits now being tested in Texas come back with results, perhaps hundreds of women may get the same knock on the door that Ellen did. It’s likely arrests will be made and, down the line, juries will have to weigh decades-old evidence. Investigators will seek out eyewitnesses from the distant past – or fail to, as lawyers in Moore’s trial did. Inevitably, these kind of cases will lead to appeals, O’Shea says, as lawyers and judges hash out key issues like statutes of limitations and defendants’ right to a timely trial.

But for Ellen and Moore, the case revived troubled times and ended like many other rape cases, old and new, with no firm conclusion. After nine years of sobriety, Ellen had suppressed her memories of the vicious attack, and then had to relive them. The identity of her attacker is still an unanswered question. “I believe with every fiber of my body that I wasn’t the first or last woman he did this to,” Ellen said in testimony, according to the Plain Dealer. And when O’Shea asked her in court if she knew her rape kit had sat untouched on a shelf for 20 years, he recalls, all she could say was, “Why?”

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