Just One DNA Sample Needed: Forensic Doctor Reveals How to Unmask Sexual Violence Perpetrators

A forensic expert, Dr Sumy Hastry Purwanti, has revealed that DNA can assist forensic teams and investigators in finding perpetrators of sexual violence. Amidst the high prevalence of sexual violence cases in Indonesia, police require certainty from various data to investigate offenders. One method involves searching for DNA on the victim’s body, a task carried out by the forensic team. Dr Sumy Hastry explained that DNA can be obtained from skin tissue, blood, saliva, hair, and bodily fluids. Even fingerprints left on a table or lipstick marks on a glass can serve as DNA samples. “DNA, if not cleaned with water or anything else, will remain attached. If I touch this table, my DNA is already stuck. If it is not cleaned, it will stick forever,” Dr Sumy Hastry stated on the Kick Andy Show YouTube channel. All such DNA can survive for a long period in dry conditions. This often leads to a case being promptly solved. Dr Sumy Hastry once helped uncover a criminal case of sexual violence on Morotai Island, North Maluku. The forensic expert performed an exhumation, or the digging up of a grave, of a 15-year-old child who had been raped. At the time, investigators did not yet know the perpetrator but suspected people close to the victim. The victim had been buried behind the family home. Dr Hastry and her team then carried out the exhumation to perform an autopsy on the body. “We dug it up, I examined it, I performed an autopsy, I took samples from inside and outside her genitals. It turned out there were still dried fluid remnants containing the DNA of her stepfather,” she explained. Even after two months of burial, DNA could still be found because the grave was in dry soil and the body had not been washed or buried properly. This resulted in a slow decomposition process, leaving the perpetrator’s DNA still present on the victim’s body. Furthermore, DNA can also be passed down to descendants, such as children and grandchildren. This high-ranking officer also once found other DNA on a victim’s body that turned out to match the perpetrator’s grandfather.