DNA hits solve cold cases, announces AG Cooper
Release date: 5/27/2004
Chewing gum, hair and even cigarette butts left at a crime scene can lead detectives to the right suspect thanks to DNA analysis. DNA, or deoxyribonucleic acid, is a unique genetic fingerprint found in every cell of the human body. Just a tiny trace of the criminal in saliva or blood left behind at a crime scene yields a DNA profile, which then can be compared to DNA samples from known criminals or other crime scene evidence for a match.
The value of DNA technology is perhaps most promising when it is used to solve crimes when there is no apparent suspect in the case. In a random rape case, for example, the victim may not be able to identify her attacker. When investigators examine evidence contained in a sexual assault kit collected from the victim, they are often able to collect a DNA sample from her attacker. This evidence can then be compared through the national DNA database, commonly called the CODIS system. If the comparison yields a match to an offender, the rapist can then be identified and brought to justice even though the victim never was able to identify her attacker.
Attorney General Roy Cooper has led a push to expand the DNA database and to examine sexual assault kits that have gone untested at police departments across the state. Since last December, North Carolina has added DNA samples from convicted felons, and just like fingerprints those DNA profiles are filed away into state and national databases of criminals. He has tripled the number of specialist agents at the SBI lab who can perform this analysis, and is asking the legislature for six more for next year.
Since criminals, and especially rapists, often strike again, a database "hit" can crack a cold case. The national DNA database has scored more than 4,500 hits since 1998 (Criminal Justice Newsletter, 2002).
However, we must do more. The National Commission on the Future of DNA Evidence says that more resources must go to law enforcement to use this technology quickly and effectively. Congress has debated helping states do more with science, but criminals who should be caught walk free. (Using DNA to Solve Cold Cases, US DOJ, July 2002).
In 1990, before North Carolina’s DNA database was established, a series of brutal attacks on elderly victims shook Goldsboro. DNA analysis showed that the same person had committed all three crimes, but police had no suspects.
Ten years later, the SBI retested the evidence with new DNA technology and compared the DNA profiles with the database. In 2001, they matched a suspect whom police would likely never have found. The suspect's DNA was included in the state database because he had previously been convicted of a violent felony. When confronted, he confessed.
Just as DNA evidence can pinpoint a criminal, it can exonerate suspects who were accused using less reliable evidence, such as eyewitness testimony or co-defendant accusations. As the technology advances, the chances of convicting an innocent person, at least where identity can be proven through biological evidence, is greatly diminished.