Nonfiction Nugget: Creative ways DNA has been used to solve crimes

Welcome to the next installment of my Nonfiction Nuggets series, which I’ll be sharing on the blog about every other month, in addition to my PI Posts, Character Coffee Chats and regular post updates.

Today’s Nonfiction Nugget is about interesting cases involving the use of DNA to solve crimes. I’ll be sharing some details about cases, so I would like to warn readers that the subject matter might be difficult for sensitive readers. Please take care as you read on and also be prepared, as some of the information I share might also offer spoilers to anyone who hasn’t yet read the Jorja Matthews mystery series. 

Some of my favorite topics to read about are real crimes with plot twists or cases solved using creative methods. In March I shared a post related to the topic of adoptions and how the use of DNA analysis can help verify blood relationships. Of course, we all know DNA is also used to assist in charging and convicting suspects, and is very helpful in solving cold cases that might otherwise remain unsolved.

The subject of using DNA to solve crimes has slipped into my mystery series and I guess I’d be a poor story teller of mysteries if I didn’t make use of it at some point. In one of the novels in my series, Ties That Bind, Jorja (a private investigator) is able to obtain a coffee cup a suspect leaves behind at a table in a coffee shop before handing it off to the police to help solve a murder. In real life, DNA and evidence collection is left up to the professionals, but when it comes to fiction we sometimes give our characters a bit of leeway when it comes to helping the authorities. However, since I spent 30 years in the legal field as a legal assistant and private investigator, I certainly do my best to make it as plausible as possible.

Some interesting cases involving DNA

For authors who write about police detectives solving crimes, there’s no shortage of ideas when it comes to how the police might use DNA to arrest a suspect. In my previous post, I shared a snippet about how law enforcement recently made an arrest in a cold case involving the death of an infant that occurred in my home state 23 years ago. The case investigation used DNA analysis in two ways…first, they narrowed down the list of possible relatives of the baby and then when they zeroed in on the suspected mother, they gathered DNA directly from her in order to verify she was a match to evidence left at the scene. How did they gather the suspected mother’s DNA? The investigators used a creative method in order to obtain her saliva, which she willingly supplied under a ruse.

The death of an infant is extremely sad, and even more disturbing is that it hasn’t been the first time we’ve heard about that type of case. In fact, my first Nonfiction Nugget post covered the topic of postpartum psychosis and mothers who harm their children. The difference is that years ago, a mother could leave a newborn to die and if there were no eye witnesses, she could walk away without getting caught. Now, DNA can help trace and track down the mother by using the baby’s DNA, whether the incident happened yesterday or twenty-five years ago. Another example involves a case from a few years ago, when a woman in Colorado was also charged with the murder of her infant child born in 1996. Investigators first used DNA from the baby to narrow down a list of possible relatives, and then with interviews they were able to narrow down the suspect to just one person.

Using gum to solve a cold case after 35 years

There’s an interesting case from 1976 where chewing gum was used to help solve a crime. You read that right: chewing gum. But the case wasn’t solved in 1976…it would take over 35 years for that to happen. The case began in Maine when concerned citizens contacted the police because one of their neighbors hadn’t been seen for a few days. When authorities entered the home of the 70-year-old woman to check on her, they found a disturbing crime scene resulting from her murder. The police had one possible suspect, a young man named Gary who had lived with the victim briefly before her death. However, he left the area and could not be found so eventually the case went cold.

The case may have begun in Maine, but it ended in Washington State many years later when one man stabbed another on Capitol Hill. While charges weren’t filed because the victim couldn’t be found, the knife was taken into evidence. Once the knife was analyzed, it was discovered that DNA on that knife matched blood from the murder scene in Maine. But was the knife-wielding man the same man responsible for the cold-case murder? The Maine investigators certainly wished to find out and asked the Seattle police to obtain a DNA sample from the suspect to verify whether he could be tied to the murder. Again, the police in this case used a creative method to obtain the suspect’s DNA sample. They located him on the streets, made contact while undercover and asked him to participate in what turned out to be a fake survey involving chewing gum. The DNA would later be used to charge him with the murder.

Not everyone wants the authorities to access their DNA

There are many, many cases solved using DNA, but the process of investigative genetic genealogy has caused some concerns and backlash. The ability to use DNA evidence to obtain information on a suspect’s distant relatives in order to identify and locate the suspect is an extremely useful method, but there was an issue when it became known that information on a consumer DNA database was accessed without the permission of the users. There’s an interesting article explaining what happened after authorities in California arrested the suspect they dubbed the Golden State Killer. While many were obviously thrilled a suspected serial killer was off the streets, many were not pleased the authorities did so after using a consumer DNA database without the express permission of the users.

 Watch where you leave your DNA…at least if you’re a criminal

Criminals are usually living in the moment and don’t think ahead of time about how to prevent getting caught. That’s a good thing, if we’re looking for the positive. The authorities don’t have to come up with creative ways to obtain DNA from a suspect when the suspect conveniently leaves it behind. One example is a burglar in Oregon who broke into a house and decided to grab some beer on his way out before heading to the house of his next victim. He carelessly tossed the beer bottle in the backyard of the second victim before climbing inside to steal her jewelry. Eventually, the DNA left on the beer bottle, and other items found at additional burglaries, was linked to a man who confessed to breaking into over 200 homes during a three–year period.

You can run, but you can’t hide from your DNA

Other examples include a man charged with the death of a train station ticket agent in Illinois after he crashed his vehicle and walked away from the scene. The DNA left behind on the airbag was compared to DNA from his residence and I expect they knew where he lived because his vehicle would have been registered to him. Another burglar from Ohio was sentenced to 28 years after his DNA was linked to multiple burglaries. The DNA he left behind was in the form of his blood, after he cut himself breaking windows in order to gain entry into the residences. And in Colorado, a Goodwill employee was shot during a robbery and the police were able to easily identify the suspect, who had a lengthy criminal history already, from the DNA found in his mask that he left near the scene of the crime.

All good (and bad) things must come to an end

Some criminals plan ahead and believe they are too smart to get caught; others commit crimes on a whim and lay low while they cross their fingers. But whether or not criminals plan ahead, eventually they all make mistakes and as the suspect who broke into more than 200 houses learned, more often than not it all comes to an end and DNA is the one piece of evidence difficult to deny. For the families waiting for news in the worst types of cases, the passing of time without answers can be heart wrenching but at least DNA evidence gives the authorities the ability, even if years from now, to give those families answers.

I hope you’ve enjoyed this installment of my Nonfiction Nuggets series and that you’ll continue to follow my blog for additional posts. If you’ve read my mystery series, check back again next week for another Character Coffee Chat. Or you can pop by next month for the next P.I. Post. (you can read the previous P.I. post here) where I share P.I. topics, unique stories and interesting case reviews beyond my Nonfiction Nuggets.

Until next time…take care and stay out of trouble!