Cutting-edge DNA Technology Tracks Down Cold Case Criminals

By Shuangming Pang


A man accused in the murder of his former Woonsocket, Rhode Island neighbor two years ago was released from jail after posting $5,000 surety on Aug 1.

Matthew Dusseault(Left) and Tyler Grenon. Courtesy of Woonsocket police

The case, which went cold after the incident on March 23, 2016, involved 81-year-old Constance Gauthier getting stabbed to death in her home. Tyler Grenon, 23, of Attleboro, Massachusetts was released after a hearing. A second suspect, Matthew Dusseault, 21, of Woonsocket R.I., remains held without bail at the Adult Correctional Institution, pending a hearing later this month.

The break that led to the arrest came when police turned to a cutting-edge DNA technology — matching DNA at the crime scene with DNA from a public genealogy website — to aid them in developing suspects.

The most well-known case to use this new DNA technique involved the man accused of being the Golden State Killer, who committed 12 homicides and 50 rapes in California beginning in the 1970s. Investigators on that case uploaded the DNA sample to a genealogy website called GEDmatch, matching it to a distant family member of the suspect, Joseph James DeAngelo.

The breakthrough in the Golden State Killer case made famous a trend to crack down cold-case criminals by using this same technology. Within three months, six more similar cases lead to charges nationwide. The Woonsocket case was the seventh such case leading to an arrest after the California breakthrough.

Parabon Nanolabs, a DNA technology company, was involved in all four cases, including the Woonsocket one. The idea of using an open-source ancestry website to crack down cold case criminals is new to law enforcement.

But some people oppose this method because of privacy concerns. The increasing interest in ancestry research prompts people to supply their DNA information voluntarily to such public DNA databases as 23andMe and

The concept of privacy surrounding DNA data has turned into a legal quandary. “I think society is probably going to struggle adjusting to this idea,” said Frederick Bieber, a Harvard professor of pathology and an expert in DNA analysis.

“There is a lot of information that is available,” Bieber said, “hopefully for good purposes, and maybe sometimes for purposes that we haven’t thought about yet. That maybe we should start thinking about.”

Bieber described the justice system of the U.S. as being a three-horse chariot: One horse is science and technology, another horse is law, and the third horse is ethics and policy. “Often the science and technology horse were racing ahead very fast, and it made a sort of rocky ride, an uneven ride in this chariot.”

For the traditional forensic investigation, the crime labs take the crime scenes’ DNA and run them through CODIS, a national criminal DNA database. The direct DNA matches happen when the owner of the DNA was previously arrested or convicted of a crime, registering his or her DNA in CODIS.

Using a relatives’ DNA to track down criminals is called Familial DNA Searching. This method searches the DNA database using software to detect a list of potential candidates who may be close biological relatives to the unknown individual.

States have laws to approve familial DNA searching only in high-profile crimes, and when other approaches have failed. Right now in the U.S., there are 12 states — Arizona, California, Colorado, Florida, Minnesota, New York, Ohio, Texas, Utah, Virginia, Wisconsin, and Wyoming — that have solved cold cases using familial DNA matching.

The Golden State Killer case showed the investigations could go further by using publicly available DNA data to identify more distant relatives to crack down on criminals.

“From the attorneys I’ve talked to, concerning this application, most jurisdictions will stand a legal challenge,” Carll Ladd, a DNA expert at Connecticut Forensic Lab said. “Since you are talking about first crime scene sample, there is no expectation with privacy. And concerning the search itself, they feel that the suspects develop the understanding of the sample that a distant relative voluntarily put into the database.”

“Definitely there are a lot of people are excited about it,” Ladd said, “Now the amount and effort required to do this genealogy searching are sufficiently great that I don’t see it being used in routine cases.” It would only be used in high profile cases where traditional DNA typing methods have not been provable, like serial homicide and serial sex assault.

Ladd said the reason that Connecticut doesn’t utilize familial DNA searching is “it will require a change to the Connecticut database law regarding sharing information in a partial match situation such as what you encounter with familial searching.” This statute, created back in the 90’s, established the Connecticut database. A change in this law requires additional legislation.

The Connecticut legislature will try again to append this law. “Hopefully the success of cases like GEDMatch would demonstrate the overall utility of familial searching,” Ladd said.

Civil libertarians are concerned about DNA testing because identification methods have improved so much over the past 10 years.”There is almost no law in this space regulating how law enforcement can access or what they can do with DNA information once they access it,” said Kade Crockford, the director of the Technology and Liberty Program at the ACLU of Massachusetts.

Since DNA contains varieties of sensitive information not only about an individual but also his or her family, lawmakers may need to look very carefully at how to frame such laws. Law enforcement should be allowed to access people’s DNA information, but only with careful restrictions on what they do with it once they possess it, Crockford said.

“In this case, it is clear that use of this technology brought an offender to account, bringing survivors and their loved ones some sense of justice. As technology continues to evolve, these discussions need to continue and deepen, and we would advocate for survivors having a voice at the table,” said Gina Scaramella, executive director at Boston Area Rape Crisis Center.

Those who express concerns about DNA and its role in the criminal justices system often make references to health records, and what insurance companies might abuse using DNA samples.

In many instances, if law enforcement gets a warrant from the court, they may be allowed to have access to information that normally would be considered private. In fact, there are some instances in which law enforcement agencies can ask the courts for a search warrant to obtain samples from a hospital patient without their knowledge or consent as an exception to federal HIPAA (Health Insurance Portability and Accountability Act) rules.  The HIPAA rules outlines privacy protections for individual health information.

About Shuangming Pang 4 Articles
Shuangming Pang is a multimedia journalist. Shuangming got the Bachelor degree in journalism at Shanghai University of Sports. She covered the 2016 Rio Summer Olympics as an intern producer of the sports channel at Shanghai Media Group, as well as a news editor of the college sports magazine during her undergraduate studies.