DNA Evidence InfoMarina DauerSkyline High SchoolRegion 8AHookWe all know the feeling. You IntroIf it’s been a while since your sixth-grade biology class, don’t worry.
WeDNA, or deoxyribonucleic acid, is the hereditary material in humans and almost all other organisms. Nearly every cell in a person’s body has the same DNA. The biological material used to determine a DNA profile include blood, saliva, urine, hair, teeth, bone, tissue and cells. Investigators collect items that could have been touched or worn by persons involved in a crimePreviewTo fully understand the complexities of DNA evidence and its use in the judicial system, we must first- sample information about DNA’s history of use in court cases, next- uncode the pros and cons of using DNA evidence, and finally- make a ruling and determine how DNA evidence should be utilized in the future.Background- What is DNA evidenceHistoryDNA profiling was originally developed as a method of determining paternity, in which samples taken under clinical conditions were examined for genetic evidence that could link parent to child. It first made its way into the courts in 1986, when police in England asked molecular biologist Alec Jeffreys, who had begun investigating the use of DNA for forensics, to use DNA to verify the confession of a 17 year-old boy in two rape-murders in the English Midlands. The tests proved the teenager was in fact not the perpetrator. However, actual attacker was eventually caught also using DNA testing.
The first DNA-based conviction in the United States occurred shortly after in 1987 when the Circuit Court in Orange County, Florida, convicted Tommy Lee Andrews of rape. The first state high court to rule in favor of admitting DNA evidence followed just two years later in West Virginia.According to Forensic Magazine, in the early years after these groundbreaking cases, the admissibility of DNA evidence was largely not disputed. That began to change once the use of DNA evidence became more popular with prosecutors. Soon, defense attorneys began to routinely challenge the admissibility of DNA tests.
In general, two standards are used to judge the admissibility of novel scientific evidence – the “Frye standard” and the “Daubert standard.” The Frye standard originates from a 1923 case, Frye v. United States, where the court ruled that, to be admissible, scientific evidence must be “sufficiently established to have gained general acceptance in the particular field in which it belongs.”The stricter “Daubert standard” is more recent. It was derived from the 1993 case Daubert v.
Merrell Dow Pharmaceuticals. In this case, the Supreme Court went beyond the Frye standard and stated that evidence must have sufficient scientific validity and reliability to be admitted as relevant “scientific knowledge” that would “assist the trier of fact.”ProsAccurate evidenceThe greatest advantage of DNA profiling lies in its specificity. Even relatively minute quantities of DNA at a crime scene can yield sufficient material for analysis. Forensic scientists typically compare at least 13 markers from the DNA in two samples. In a test with 13 markers, the probability that any two individuals would have identical profiles is estimated to be below 1 in 10 billion.
Consequently, when specimens are collected properly and the procedure is performed correctly, DNA profiling is an extremely accurate way to compare a suspect’s DNA with crime scene specimens.Can exonerate people after the factDue to the biometric nature of DNA evidence, it can be used to exonerate people long after they are convicted. This pattern of verdict reversal through the use of DNA evidence has been seen many times in the past few decades. Stuart Taylor Jr.,Senior Fellow of Governance Studies at the Brookings Institution, stated “Irrefutable DNA evidence has exonerated some 15 death-row inmates and almost 200 other men convicted of murder or rape, mostly since the late 1990s. This DNA-evidence revolution… has alerted many who support the death penalty in principle to the fallibility of the criminal-justice system and the risk of executing innocent people.” in an Nov. 17, 2007 article for the National Journal.
Cons”CSI effect”DNA evidence is only one of many types of evidence jurors should take into account when considering a case. TV shows like “CSI” may have popularized forensic science to the point where some jurors have unrealistic expectations of DNA analysis and give it more weight than other types of evidence. This phenomenon is called the “CSI effect.”Ethical Questions How we should utilize itConclusion