Serial killers often inspire a mix of both fear and fascination. It’s hard to imagine how one person could be capable of committing so many criminal acts—and how they can get away with them in the first place.

But what about serial rapists? Although we don’t hear about them in the media nearly as often, statistics from the Rape, Abuse & Incest National Network (RAINN) suggest that serial sexual predators are not at all uncommon. In fact, more than half of alleged rapists have at least one prior conviction for rape, robbery, assault or battery.

Too Many Unprocessed Rape Kits

Part of the reason so many serial rapists go unprosecuted is the rape kit backlog, says Leonard Sipes, founder of crime stats website CrimeinAmerica.net and former senior crime-prevention specialist for the Department of Justice’s clearinghouse: “There are thousands that go unprocessed for a multitude of reasons.”

A rape kit is an exam administered by medical professionals to collect DNA and forensic evidence after an alleged sexual assault. The results often prove invaluable to prosecutors, but current estimates indicate that more than 200,000 rape kits in the U.S. still remain untested.

One of the main reasons, says Sipes, is cost. While rape kits are free for the victim, each one can cost up to $1,000 to $1,500 to administer. In addition, detectives and prosecutors might not order the kits to be tested, or the forensic evidence might simply languish in a crime laboratory. Rape kits often aren’t counted, monitored or recorded effectively.

Breaking the logjam

Federal funding for rape kit testing through the Sexual Assault Kit Initiative (SAKI) has begun to address the problem, providing $154 million for rape-kit processing in 54 jurisdictions nationwide starting in 2015. In Wayne County, Michigan, Prosecutor Kym Worthy launched a fundraising initiative, Enough SAID, to underwrite testing for around 10,000 of the more than 11,000 rape kits discovered languishing in a Detroit police warehouse. The program staggering results, uncovering 817 serial rapists, more than 50 of whom were linked to between 10 and 15 ongoing sexual-assault cases. Worthy told the Detroit Free Press that “a rapist rapes on average seven to 11 times before they’re caught.” Some re-offend while out on bail while awaiting trial.

A 2016 federally funded rape kit testing program through Case Western Reserve University in Cuyahoga County, Ohio, had similar results. More than half of the DNA specimens in the rape kits tested were traced back to prior sex offenders.

DNA is what finally brought 52-year-old Alfred Berry to justice for sexual assaults he committed in New Orleans in the 1980s. Berry was already a Louisiana inmate for armed robbery when, in 2019, he was finally convicted on six counts of kidnapping women, raping them at knifepoint and gunpoint, or binding them and taking them to secret locations to assault them.

And although he’d been accused of sexual assault several times before his incarceration for armed robbery, Berry always escaped conviction. One of his victims died of suicide after the jury reached a deadlock in her rape case against Berry, and he was acquitted in another rape case in 1988.

Preserved DNA evidence, which couldn’t be reliably tested when Berry’s victims first came forward, finally caught up with the serial predator. Berry pled guilty to six counts of second-degree rape and second-degree kidnapping, reduced from first-degree rape and aggravated kidnapping as part of his plea deal. He was sentenced to 35 years in prison in September 2019. His victims, who delivered emotional impact statements at Berry’s trial about how his assaults haunted them for years to come, reportedly hugged each other in relief after court.

Helping Victims without Retraumatizing Them

But catching serial rapists takes more than DNA evidence. In fact, it isn’t even collected in around half of rape cases, partly because many victims understandably find the invasive, hours-long process of a rape kit upsetting. Stigmatization of rape victims also contributes, says California-based forensic psychiatrist Dr. Carole Lieberman. Victims’ fears of being dismissed, disbelieved or retraumatized might push them not to report, or to report too late for forensic evidence to be collected.

“More serial rapists could be caught if there were more female police officers, so that women would feel more comfortable coming forward,” Dr. Lieberman suggests, or if “high schools and college did more to protect women, such as by having more safety officers, and believed rape victims more.”

Another way to help law enforcement apprehend more serial rapists, advocates say, is to do more work tracking criminals’ behavioral patterns. But, according to ProPublica, the FBI database created to do just that—the Violent Criminal Apprehension Program, or ViCAP—often goes unused.

Ultimately, Sipes argues, serial rapists often take advantage of the criminal justice system’s flaws by reoffending. Some flee to different jurisdictions to target new victims, for example, because they know that police departments might not communicate efficiently across state lines. “Serial rapists understand these issues,” he says, “and it prompts criminality.” Many predators, it seems, know there’s a high chance they will get away with their crimes simply because they and so many other serial rapists have before.

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