Special Feature: Forensic Sciences
The term "forensic science" covers a broad range of forensic disciplines, each with its own set of technologies and practices. Some are laboratory based, while others are based on expert interpretation of observed patterns.
In recent years, the extensive use of biological evidence to identify victims and offenders has had a significant bearing on the course of law enforcement investigations, criminal court proceedings, and victim service provider issues. The impact of forensic science evidence can often be the difference between acquittal or conviction in the mind of a juror.
DNA evidence has arguably become the most well-known type of forensic evidence, since it is the genetic blueprint of the human body and can be uniquely identifying. The development of DNA technology furthers the search for truth by helping police and prosecutors in the fight against violent crime. Through the use of DNA evidence, prosecutors are often able to conclusively establish the guilt of a defendant.
An unforeseen effect of the introduction of DNA profiling has been the reopening of old cases. In some instances, DNA test results have exonerated those convicted of the offenses and resulted in their release from prison. The National Institute of Justice has long supported states and local governments with funding to identify, review, and investigate cold cases with the potential to be solved using DNA analysis. And, in 2019, NIJ shifted the focus of its Solving Cold Cases with DNA program to the prosecution of violent crime cold cases where DNA has been used to identify a suspect.
But the increased demand for forensic DNA casework has also overwhelmed laboratories and their ability to test this evidence in a timely manner. With new technology and innovative methods, laboratories have become more efficient and can process results more quickly, but as technology becomes more helpful to law enforcement agencies, more and more DNA evidence is sent for analysis.
This issue is evidenced by the backlog of sexual assault kits (SAK) that some jurisdictions around the country are struggling with.
A SAK is the cornerstone of any sexual assault investigation, potentially holding critical DNA evidence for law enforcement, but there are mounting backlogs of untested kits, some dating back to the mid-1970s. The National Sexual Assault Kit Initiative (SAKI) from the Bureau of Justice Assistance is one effort from the Office of Justice Programs aimed at reducing the backlog of SAKs. Since 2015, more than 200,000 unsubmitted kits across 54 jurisdictions in 35 states have been identified through SAKI and more than 47,000 of these have been tested.
DNA technology and forensic science, as a whole, have revolutionized the criminal justice system. These methods have given police and the courts a means of identifying the perpetrators of rapes, murders, and other crimes with a very high degree of confidence.
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