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DNA in Criminal Investigations

Introduction

DNA sampling has been identified as one of the most reliable methods of collecting convincing evidence against a suspect at a crime scene. This is because human DNA does not resemble when the 13 loci are analyzed. Most importantly, a DNA sample is readily found at the crime scene; thus, it is collected and run in the national database so as to identify its match. It is noteworthy that as time goes by the use of DNA samples in criminal investigations has also been advancing. Previously forensic investigators employed the ‘restriction fragment length polymorphism’ (RFLP) technology, but, at the moment, the ‘short tandem repeat’ (STR) technology is mostly employed.

RFLP and STR

Bell, (2004) reveals that the ‘Short Tandem Repeat Technology’ (STR) is used in the appraisal of precise areas within nuclear DNA. One DNA profile can be distinguished from the other by considering the unpredictability in STR regions. The federal bureau of investigation (FBI) put in to employ a set of 13 detailed STR regions for ‘combined DNA Index System’ (CODIS), a software plan that picks from communal, state and countrywide databases of DNA profiles of lost persons, unsettled transgression scene substantiation and inmates in correctional facilities (Bell, 2004).

It is noteworthy that in ‘restriction fragment length polymorphism’ (RFLP) that was used before elongated chains of inveterate bases are examined, whereas the currently used STR looks at similar fact on a lesser scale (Bell, 2004). In addition, RFLP needs a huge quantity of samples, while STR allows for assessment of explicitly repeated units of DNA within a sample; thus, when this is matched with PCR it can be performed on smaller samples. Additionally, in the previously used RFLP an old taster or that besmirched by ecological factors is not apposite for this process, but in STR old or degraded samples can still be used to give reliable investigation outcomes (Bell, 2004).

DNA used in criminal investigation today

Any person can be identified through the evaluation of DNA series distinctive to that individual. In addition, identifying criminals at a transgression scene is less accurate at the moment; however, as DNA sequencing technologies progress more direct evaluation of outsized DNA segments, and maybe whole genomes will become probable and realistic thus allowing precise criminal identification. At a crime scene, the forensic investigators accumulate dissimilar samples of DNA and scrutinize 13 DNA loci a model which differs in human beings. This is then used in the construction of the person’s DNA fingerprint.

Most importantly, there is a diminished chance that people can have equivalent DNA fingerprints for a precise set of 13 regions (Lazer, 2004). According to Bertino, and Bertino, DNA evidence in the criminal examination is used for the determination of culpability and exclusionary. In circumstances where more than one person is involved in the transgression scene, the court will issue court orders for DNA resolve of each one of them. In case the DNA consequences fall short to match any of the suspects, they are expelled from the inquiry. However, if it matches the individual’s, then the DNA substantiation is a sturdy case against that suspect (Bertino and Bertino, 2008).

Impact of DNA on the criminal justice system

Gaines and Miller (2008) have confirmed that DNA has made an impact on the examination and resolve of criminal cases, which includes, the way suspects are fortified and prosecuted in a court of law. Many people accept although reluctantly that use of DNA evidence in criminal prosecution is a broad step taken towards the advancement of the criminal justice system. DNA is diverse because of its effect on the connotation of time. Thus, DNA can be analyzed long after its deposition on a crime scene. As a result, it overcomes all the obstacles concerning time limits and prosecution limits. Hence, the new evidence can be brought forth long after conviction.

Moreover, DNA can twirl up information and match a sample to the one present in a crime scene by confirming the identity of the source. It has been noted that in any criminal process DNA has the most influence throughout the examination of the situation and case and also after the fervor of the suspect, but not during the trial of the suspect. However, some experts have argued that the use of DNA as evidence against a suspect is not a reliable mode of conviction. Most importantly, they argue that DNA results can easily be tampered with and, as a result, a case can be judged unfairly. Despite these negative opinions, there is enough evidence to confirm that DNA has completely revolutionized the criminal justice system (Gaines and Miller, 2008).

Conclusion

It has been evident the use of DNA in criminal investigation has advanced over time and, as a result, most investigation bureaus around the world consider it a reliable investigation tool. It is noteworthy that many suspects have been convicted, and some acquitted of the charges by the use of DNA evidence during the trial. However, experts warn that the use of this technology is not reliable as the DNA samples are easily manipulated thus providing wrong information. In addition, there are others who argue that this technology comes with more advantages than disadvantages.

References

Bell, S. (2004). The facts on file dictionary of forensic science. New York: InfoBase Publishing.

Bertino, A. and Bertino, P. (2008). Forensic Science: Fundamentals and Investigations. Ohio: Cengage Learning.

Gaines, L. and Miller, R. (2008). Criminal Justice in Action: The Core. New Jersey: Cengage Learning.

Lazer, D. (2004). DNA and the criminal justice system: the technology of justice. Massachusetts: MIT Press.