Dna Profiling Strengths And Weaknesses

This paper explores deoxyribonucleic acid (DNA) collection and its relationship to solving crimes. The collection of DNA is one of the most important steps in identifying a suspect in a crime. DNA evidence can either convict or exonerate an individual of a crime. Furthermore, the accuracy of forensic identification of evidence has the possibility of leaving biased effects on a juror (Carrell, Krauss, Liberman, Miethe, 2008). This paper examines Carrells et al’s research along with three other research articles to review how DNA is collected, the effects that is has on a juror and the pros and cons of DNA collection in the Forensic Science and Criminal Justice community.

DNA analysts have been profiling DNA since 1985. Then in 1998, the Combined DNA Index System became fully operational (“FAQs” 2010). CODIS’s three levels are the national level, the state level, and the local level. As September 2015, there is 14,740,249 DNA profiles in CODIS (“CODIS”, n.d.). Since everybody has different DNA, except identical twins, DNA analysts have been able to assists with investigator to determine between who is guilty and who is innocent. With some of their findings, they are able to exonerate individuals, who have been wrongfully convicted. Even though television may make DNA analysts’ life look simple on the screen, it is not. There is need for interest and education. Lastly, the actual job that entails for the DNA

. DNA profiling was first introduced to the criminal justice field in the mid-1980’s (DNA Initiative). DNA profiling was first described in 1984 by Alec Jeffreys, a geneticist at the University of Leicester in Britain (Aronson, 7). Dr. Jeffreys found that the genes that have no function, called “junk DNA” is where most of the variation is used for DNA profiling (Aronson 9). This region contains DNA sequences that repeat over and over again. Alec Jeffreys determined that the number of repeated sections at different locations vary from individual to individual (DNA Initiative). Consequently these repetitive regions became known as “variable number of tandem repeats” or VNTR’s.

DNA testing was first used in criminal prosecutions in 1985 and is now admissible in all states. (Hails, 184) Scientific and legal communities seem to universally accept the use of DNA as “good” evidence. Questions could arise regarding testing procedures. There are several testing methods that have been proven reliable and easily pass general acceptance and scientific validity tests. This is causes number of Daubert cases questioning DNA to decline. “In most cases, the tests that are used are well established and do not require a separate hearing” (Hails, 160)

forensic identification technique today1. It is the case of analyzing and profiling a DNA sample

I. Before the 1980’s, courts relied on testimony and eyewitness accounts as a main source of evidence. Notoriously unreliable, these techniques have since faded away to the stunning reliability of DNA forensics.

DNA testing is a critical and accurate tool in linking accused and even convicted criminals for crimes, and should be widely used to assess guilt or innocence before jail sentences are imposed. It was started up by scientists Francis C. Crick and James D, Watson in 1953 as they had described the uses, structures and purpose of the DNA “deoxyribonucleic acid” genetic fingerprint that contains organism information about an individual (testing

Today in the crime world, DNA evidence is strongly accepted in solving crime cases. This is all based in part by allowing a crime laboratory to have a designated unit whose main goal is to analyze DNA evidence to aid investigators with positive outcomes in crime case solving. With that being said we are going to discuss the functions of a DNA unit within a crime lab as well as address the vital role these units play in solving crime.

Due to the uniqueness of DNA it has become a powerful tool in criminal investigations

DNA forensics can also narrow down suspect pools, exonerate innocent suspects, and link crimes together if the same DNA is found at both scenes. However, without existing suspects, a DNA profile cannot direct an investigation because current knowledge of genotype-phenotype relation is too vague for DNA phenotyping. For example, a profile from a first time offender that has no match in any database may give the information that the criminal is a left handed male of medium stature with red hair and freckles. It would be impossible to interview every man who fits that description. However, with available suspects, DNA forensics has many advantages over other forms of evidence. One is the longevity of DNA. Although it will deteriorate if exposed to sunlight, it can remain intact for centuries under proper conditions (Sachs, 2004). Because DNA is so durable, investigators can reopen old cases to reexamine evidence.

Every day DNA technology becomes more advanced and innovative, for example can match the smallest amounts of biological evidence to a criminal offender. Future DNA techniques will be applied to existing systems and testing methods that will become more automated and will be more effective and less time consuming. Instead of waiting months of DNA results the future will provide instantaneous means for DNA profile development.

DNA profiling technologies have had a considerable impact on how forensic science and criminal investigation have been understood, carried out, and regulated in the last 25 years. Current methods of forensic DNA profiling (known also as DNA fingerprinting and DNA typing), based on Polymerase Chain Reaction (PCR) amplifications of a varying number of Short Tandem Repeat (STR) loci found at different locations on the human genome, are regularly described as constituting the “gold standard for identification” in contemporary society. Prior to the implementation of PCR based extraction and amplification methods in the 1990’s, the initial uses of DNA fingerprinting (based on Multiple and Single Locus Probes) were largely confined to reactive

Another report from Turman, herarticle about the importance of DNA evidence to say in a strong and definite way that the offenders or to prove prisoner in criminal cases has arose in the media with the developing regularity over the last few years. Criminal justice professionals and the public behold that the forensic DNA technology is reforming

Law Enforcement keep notes on arrests that have founded people innocent of crimes, and retention of an innocent person's DNA can be charge or otherwise, seen as a invasion of that person’s privacy and civil liberties. Dr. Alec Jeffrey, a former professor at the University of Leicester laboratory, consulted with his lawyers to develop the new type of technique called DNA profiling. His technique would prove that DNA fingerprinting (profiling) can individualize evidence compared to the blood typing. DNA profiling compares 13 standard STRs to form a profile. The analysis used by the scientists, uses PCR and STRs to profile an individual. It is highly unlike that two individuals’ identical numbers of repeats for all 13 STRs, will match, which DNA fails is hardly never due to a successful match of 385 million to 1. This makes DNA profiling the most accurate tool in Forensics.

Recent advancements in DNA technology have improved law enforcement’s ability to use DNA to solve old cases. Original forensic applications of DNA analysis were developed using a technology called restriction fragment length polymorphism (RFLP). Although very old cases (more than 10 years) may not have had RFLP analysis done, this kind of DNA testing may have been attempted on more recent unsolved cases. However, because RFLP analysis required a relatively large quantity of DNA, testing may not have been successful. Similarly, biological evidence deemed insufficient in size for testing may not have been previously submitted for testing. Also, if a biological sample was degraded by environmental factors such as dirt or mold, RFLP analysis may have been unsuccessful at yielding a result (Turman).