In July of 2009, the bodies of 43-year-old Alan Grna and his 85-year-old mother Julianna were discovered in their Ohio home—both victims of a violent assault. The lead detective in the case called in the Ohio Bureau of Criminal Identification and Investigation (BCI) to collect evidence from the crime scene, evidence that would lead them to the man who was eventually convicted of their murders. One of the key pieces of evidence was a roll of toilet paper.
While recording and cataloging items at the crime scene, investigators found blood spots on the Grna’s bathroom floor, toilet and soap dispenser as well as diluted bloodspots on the sink. Apparently, the perpetrator had made an effort to wash up after bludgeoning the mother and son to death. Suspicious that the murderer had used a nearby roll of toilet paper to dry his hands, a BCI special agent ordered the roll of toilet paper as well as swabs of the sink handles be collected and submitted for DNA analysis. While toilet paper seems an odd sample type, forensic labs receive all sorts of strange submissions for DNA analysis. BCI analysts were not fazed. They used swabs to collect DNA from the cardboard tube inside the toilet paper roll and generate a DNA profile that could be used to incriminate and, hopefully, identify the last person to see Alan and Julianna Grna alive.
While forensic scientists were analyzing the DNA, police received information that caused them to focus their attention on a man named Johnnie Cook. Cook was seen driving the Grna’s stolen car, he had pawned Julianna’s wedding ring and he had made phone calls to friends and family from Mr. Grna’s cell phone. Cook denied any involvement in the crime and asserted that he had never been in the Grna’s home. He voluntarily submitted a DNA sample, believing a DNA test would clear his name. However, rather than exonerate him, the DNA evidence further implicated him in the double murder. DNA collected from the toilet paper roll matched three people: Alan Grna, Julianna Grna and Johnnie Cook. The probability that DNA taken from the crime scene would match that of Johnnie Cook at random was 1 in 70 million.
Based on all of the evidence, Cook was arrested and convicted of aggravated murder, aggravated burglary, grand theft, theft from the elderly and theft. He was sentenced to life in prison without the possibility of parole and is now in prison facing the death penalty, thanks in part, to a roll of toilet paper.