Informative Speech On Dna Testing

This paper examines Carrell et al’s research along with three other scholarly research articles to better understand the effects that the DNA recovered from a crime scene has on a particular case and the forensic science community.

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)

In some cases, such as murder there are some people that have been wrongfully accused. Due to wrongful practices, people have been convicted of circumstantial evidence. ``DNA is a very powerful tool . . . but it is circumstantial evidence like other pieces of circumstantial evidence and a proper investigation still has to take place,'' she said. (Matthew, n.d.).

Beginning in the mid-1980s, the development of DNA analysis technology has revolutionised the field of forensic science within the criminal justice system. As the refinement of procedures and technology continues, even minute samples of biological material (including blood, saliva, semen and skin cells) are able to be analysed and used to link or acquit perpetrators of crimes. (Whitney, R n.d.)

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

Forensic evidence has been shown to be reliable due to many factors of evidence such as DNA, blood, fingerprints, etc.; however, many cases have shown that

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.

Deoxyribonucleic acid (DNA) has been used to analyze and prove innocence or guilt of suspects of crimes with great accuracy. DNA is part of everyday life. It is the heredity material in humans and almost all other organisms. While being part of an investigation. DNA has helped to solve crimes. There is a couple ways that DNA left behind can be tested to solve a crime. Either if the suspect has been caught and or had his or her DNA tested, or if he or she has left behind any biological evidence. Which then needs to be tested to see if it matches the DNA found in the crime scene to his or hers DNA. The result to this comparison may help establish if the suspect committed the crime.

There have been many incidents where cases have needed a solid prosecution in order to convict the defendant in a murder or rape case. This is where DNA Testing comes in to help. By taking a DNA test, a person can be found guilty or not guilty. If a person claims they have been raped there can be a sperm sample taken from the suspect in order to prove that he is guilty or not. In addition, in a murder case there can be blood taken from the suspect so they can tell of his innocence. There are several ways to determine whether a person is guilty or not by this method. Many cases have begun to use this method saying that it is foolproof. People say this is the method of the future of crime

DNA evidence is extremely helpful in criminal trials not only because it can determine the guilt of a suspect, but also because it can keep innocent people from going to jail. The suspect must leave a sample of their DNA at the crime scene in order for testing to occur, but DNA can be found in the form of many things such as semen, blood, hair, saliva, or skin scrapings. According to Newsweek, "thousands of people have been convicted by DNA's nearly miraculous ability to search out suspects across space and time… hundreds of innocent people have also been freed, often after years behind bars, sometimes just short of the death chamber" (Adler ). Though some may think it is a waste of time to go

With regard to the US, where social science and STS research have, focused less on forensic databases and more on the production of expertise and evidence in court, Jay Aronson provided a historical account of the early practices, the scientific and legal controversies, and the ultimately successful acceptance of forensic DNA evidence in court in 2007. Another particularity of social science and STS research in this domain is that it has so far mostly concentrated its “high end” forensic technologies, namely those which received a lot of public attention because they were new, because stakeholders in the criminal justice system struggled to determine the parameters of scientific reliability and admissibility, or because they were prominently featured in the media. While the use of DNA analysis for police investigations and forensic casework dates back to the late 1980s, the second half of the 1990s marked the beginning of the quest to render DNA profiles systematically and routinely searchable and minable by setting up centralized DNA databases in many countries around the world. A DNA molecule is a long, twisting chain known as a double helix. DNA looks pretty complex, but it's really made of only four nucleotides: Adenine, Cytosine, Guanine, and Thymine. These nucleotides exist as base pairs that link together like a ladder. Adenine and Thymine always bond together as a pair, and Cytosine and Guanine bond together as a pair.

Forensic science, today according to Different Types of DNA, (n.d.), can be used to determine the elements of biological evidence to solve crimes and bring closure to other legal battle. Different Types of DNA further added, because human DNA is incomparable, and DNA testing can verify individuals bringing certainty to unanswered questions, forensic science was able to influences different areas of society. With this type of certainty, forensic science is use by law makers to provide various types of DNA outlined view, such as: DNA profiling, prenatal paternity, and paternity testing, (Different Types of DNA). DNA profiling is accomplished through the analysis of one's DNA from the swabbing of the inner portion of their mouth. Prenatal paternity test, this can be achieved through swabbing of DNA from the mother and father for buccal swab. And lastly, paternity testing, a process that can be conducted on pregnant women through Chorionic Villus Sampling to resolved growth

In the science text DNA analysis the author Richard Platt describes how scientist uses DNA analysis daily. DNA is useful to solve crimes, but also if two people have the same DNA is going to be hard to find them. Scientist use DNA to solve crimes. If scientist find hair strands they send it to the lab to find who’s hair it is. Some scientist get that hair strand and maybe it’ll help them more if there’s a lot of DNA.

Sir Alec Jeffreys’ 1984 discovery of DNA fingerprinting in England has revolutionized the criminal justice system by enabling legal entities to determine innocence or guilt of a suspect to a much higher level of accuracy(Butler). This discovery has also provided the ability to identify victims of natural disasters or catastrophes like 911(Lippincott). Additionally, DNA testing or profiling, has helped doctors and researchers to identify medical conditions and illnesses, determine pre-existing conditions and prevent them sometimes before they actually occur(Roewer). Also, DNA could be separated from different individuals in mixed stains like, when two or