This article discusses sexual assault. If you are a survivor of sexual misconduct, BYU has extensive resources to help: https://advocates.byu.edu
In cases of groping sexual assaults, assailants often leave behind frustratingly little physical evidence by which they can be identified and prosecuted, or so it’s commonly believed. But it turns out, scientists can sometimes develop a full DNA profile using only the skin cells attackers shed on the victims they assault.
It’s called “touch DNA analysis,” and forensic experts have been refining the technique for nearly 25 years. Yet, many law enforcement officers and healthcare providers remain unaware that bodily fluids are not the only source of useful DNA samples, and they neglect to collect critical evidence from groping survivors’ clothing and skin.
For the past 10 years, BYU nursing professor and certified sexual assault examiner Julie Valentine has been on a mission to change that through research and education. Valentine’s work has helped put Utah at the forefront of making touch DNA evidence collection a standard practice in groping cases.
“We really see this as being a gamechanger in adding something else to the toolbox for prosecuting sexual assault cases, which then leads to safer and healthier communities,” Valentine said.
Valentine became interested in the potential of touch DNA after a 2011 breakthrough case in Utah, when a young woman was violently groped, but the assailant left no bodily fluids that could be tested. Luckily, the forensic nurse performing the woman’s medical exam recalled what she had recently learned about the newest developments in touch DNA analysis. The nurse made a report of everywhere the woman remembered being touched and collected her clothing.
“Then the nurse called the crime lab forensic scientist and said, ‘You’re going to think I’m crazy, but this is a really concerning case, and so I gathered this evidence,’” Valentine explained. “And the forensic scientist said, ‘Well, I guess this will test what we can actually do.’”
From the samples, the lab developed the assailant’s full short tandem repeat (STR) DNA profile — the gold standard, because STR profiles can be matched in the FBI’s database — and the lab profile matched the DNA of the main suspect. The sample was the lynchpin in successfully prosecuting the case.
Inspired by that outcome, Valentine teamed up with forensic nurses and forensic scientists, supported by the National Institute of Justice and its Forensic Technology Center of Excellence (administered through an award to RTI International), to design a standard form for Utah sexual assault medical examiners to collect touch DNA evidence from survivors’ skin and clothing. The form now serves as a template nationwide.
Once the form became widely used in Utah, Valentine and her colleagues drew on the emerging data from the state to confirm that touch DNA evidence can accurately identify groping perpetrators. In the first research using real-life cases, they demonstrated that out of 42 sexual assault kits collected from groping survivors, the perpetrator’s full or partial STR DNA profile could be developed from shed skin cells in six cases.
“While six out of 42 doesn’t look like a huge percentage,” Valentine said, “it is when you consider what catching even one of these perpetrators means for survivors and for communities, especially since uncaught perpetrators often repeat the offense and escalate in violence over time.” The full results of the touch DNA analysis by Valentine are published in the Journal of Forensic Nursing.
In addition to presenting the group’s findings at conferences and webinars, where they consistently encounter international interest in what they have to share, Valentine and her colleagues have also launched a massive campaign to educate law enforcement agencies about collaborating with forensic nurses and scientists in groping cases. They’ve conducted over 100 training sessions so far.
“We hope that encouraging law enforcement to have touch DNA collected will increase justice in these cases,” Valentine said. “But we also want to emphasize that groping sexual assaults are traumatic events in an individual’s life. Having survivors meet with a forensic nurse and a sexual assault survivor advocate validates to those survivors that they’ve experienced something traumatic and that we are here to help you heal.”
Earlier this year, Dr. Julie Valentine was featured in the BYU Magazine video below, where she talks about events that impacted her decision to go into her field of work and study.