The Role of Forensic Science in the Criminal Investigation

When it comes to investigating crime, no matter the level of severity, nothing is more valuable to a criminal investigator than the use and implementation of forensic science. The results of such forensic investigations can be the difference between acquittal and conviction in a court of law. The single best aid that forensic scientists use is DNA, which has proven to be a powerful tool in the fight against crime. DNA evidence can identify suspects, convict the guilty, and exonerate the innocent.

Throughout the Nation, criminal justice professionals are discovering that advancements in DNA technology are breathing new life into old, cold, or unsolved criminal cases. Evidence that was previously unsuitable for DNA testing because a biological sample was too small or degraded may now yield a DNA profile. Although DNA is not the only forensic tool that can be valuable to unsolved case investigations, advancements in DNA technology and the success of DNA database systems have inspired law enforcement agencies throughout the country to reevaluate cold cases for DNA evidence. In the next few pages I am going to talk about the importance of forensics in criminal investigations and how the two are tied together.

Let me start off with an example of how forensics helped solve a case that went unsolved for 10 years and still would have been a “cold case” had it not been for the help of DNA. In 1990, a series of brutal attacks on elderly victims occurred in Goldsboro, North Carolina, by an unknown individual dubbed the “Night Stalker.” During one such attack in March, an elderly woman was brutally raped and almost murdered. Her daughter’s early arrival home was the only thing that saved the woman’s life. The suspect fled, leaving behind materials intended to burn the residence and the victim in an attempt to conceal the crime. In July 1990, another elderly woman was brutally raped and murdered in her home. Three months later, a third elderly woman was raped and stabbed to death. Her husband was also murdered. Their house was burned in an attempt to cover up the crime, but fire/rescue personnel pulled the bodies from the house before it was engulfed in flames. When DNA analysis was conducted on biological evidence collected from vaginal swabs from each victim, authorities concluded that the same perpetrator had committed all three crimes.

However, there was no suspect. For 10 years, both the Goldsboro Police Department and the crime laboratory refused to forget about these cases. With funding from the National Institute of Justice, the crime laboratory retested the biological evidence in all three cases with newer DNA technology and entered the DNA profiles into North Carolina’s DNA database. This would allow the DNA profile developed from the crime scene evidence to be compared to thousands of convicted offender profiles already in the database. In April 2001, a “cold hit” was made to the perpetrator’s convicted offender DNA profile in the database. The perpetrator had been convicted of shooting into an occupied dwelling, an offense that requires inclusion in the North Carolina DNA database. The suspect was brought into custody for questioning and was served with a search warrant to obtain a sample of his blood. That sample was analyzed and compared to the crime scene evidence, thereby confirming the DNA database match. When confronted with the DNA evidence, the suspect confessed to all three crimes. Mark Nelson, special agent in charge of the North Carolina State Crime Laboratory, said, “Even though these terrible crimes occurred more than 10 years ago, we never gave up hope of solving them one day.” Every law enforcement department throughout the country has unsolved cases that could be solved through recent advancements in DNA technology. Today, investigators who understand which evidence may yield a DNA profile can identify a suspect in ways previously seen only on television. Evidence invisible to the naked eye can be the key to solving a residential burglary, sexual assault, or murder.

When properly documented, collected, and stored, biological evidence can be analyzed to produce a reliable DNA profile years, even decades, after it is collected. Just as evidence collected from a crime that occurred yesterday can be analyzed for DNA, today evidence from an old rape kit, bloody shirt, or stained bedclothes may contain a valuable DNA profile. These new analysis techniques, in combination with an evolving database system, make a powerful argument for the reevaluation of unsolved crimes for potential DNA evidence. Knowledgeable law enforcement officers are taking advantage of powerful DNA analysis techniques by investigating crime scenes with a keener eye toward biological evidence. The same new approach being applied to crime scene processing and current case investigation can be applied to older unsolved cases. Law enforcement agencies across the country are establishing cold-case squads to systematically review old cases for DNA and other new leads. Also DNA database systems, advancing technology, and cooperative efforts can enhance unsolved case investigative techniques like never before. Advancements in DNA technology have led to significant changes in many States’ statutes, which may affect the manner in which unsolved cases are investigated, filed, and prosecuted. Advancements in the technology have been so significant that laws are being created, amended, and even repealed to take advantage of its ability to identify and convict the guilty and exonerate the innocent.

In conclusion, forensics and especially DNA have played a vital role in aiding criminal investigators around the world. Without such advances in technology many of the cases that were solved would have still been “cold” and the offender would still be on the street, helplessly preying on other victims. If society as a whole wishes to keep the crime rate down and seek justice where it applies then we must stay on the DNA bandwagon.

Did you like this example?

414

22