DNA Analysis Abstract

This paper discusses the history of DNA analysis, how it came about, how it was first used in a criminal case, and some of the limitations of DNA analysis as shown by later criminal cases. It looks at how DNA analysis is currently used today, including a recent criminal investigation in Europe in which DNA analysis played a crucial role, and provides a description of the various directions that DNA analysis could be taken in the future in the field of forensics. The paper concludes with a summation of the main points of the paper.

Keywords: dna analysis, dna profiling, dna forensics, dna criminal justice history

Introduction

DNA analysis, also known as DNA fingerprinting in the beginning, came about in the latter half of the 20th century through breakthroughs in scientific investigation. It has been used in forensics ever since and is defined as “comparison of the DNA in a person’s nucleated cells with that identified in biological matter found at the scene of a crime or with the DNA of another person for the purpose of identification or exclusion” (Roewer, 2013). DNA analysis is now a common tool of criminal justice and is used in forensics to help identify suspects and in some cases to clear others. This paper will provide the history of DNA analysis, how it is used today, and what the future holds in store for this area as a tool for the field of criminal justice.

History

Alec Jeffreys made the first discovery of the method of DNA analysis in the mid-1980s in the UK (Jeffreys, Wilson & Thein, 1985). Jeffreys was working on identifying “simple tandem-repetitive regions of DNA (or ‘minisatellites’)” that occurred in the human genome sequence and were unique to individuals (Jeffreys et al., 1985, p. 76). He developed a method of identifying “sets of hypervariable minisatellites to produce somatically stable DNA ‘fingerprints’ which are completely specific to an individual (or to his or her identical twin)” (Jeffreys et al., 1985, p. 76). In 1987, DNA analysis was used in a case to bring to justice Colin Pitchfork who confessed to raping and murdering two girls in an English village in the 1980s. Trace DNA from semen samples obtained at the scenes of the crimes was used to make Pitchfork’s DNA profile was matched to the DNA from the crime scene. It was the first time in history DNA analysis was used in a forensics case and its arrival had a spectacular effect, particularly among interdisciplinary studies, as the utility of DNA fingerprinting in criminal justice was evident, as it had allowed for the exoneration of one suspect and let to the conviction of the actual perpetrator.

In the 1990s, DNA analysis began receiving a great deal more of attention, as the application of this type of analysis stretched far and wide. Jeffreys’ original system was re-engineered to be simpler, automated and more effective. DNA fingerprinting became known as DNA profiling, and the process of DNA analysis became a staple of forensics laboratories all over the globe. However, DNA analysis is only one step in...

J. Simpson case showed, there are ways around getting DNA evidence accepted in court or regarded by a jury—especially if doubts about chain of custody can be risen. Two cases in particular helped to show the limitations of DNA analysis and its applicability in criminal justice: the case of People vs. Castro in New York in 1989, in which the Court found that DNA analysis was more useful in exclusion than in inclusion, and the case of Amanda Knox in Italy in the 2000s (Roewer, 2013), which similarly examined the limitations of DNA analysis in pinpointing the exact identity of a perpetrator of a crime.
As DNA analysis is still somewhat new to the field of criminal justice, being under four decades old, there is much room for growth, both as a professional tool that can be reliably used in criminal investigation and in terms of social acceptance. DNA analysis has played a large role in high-profile criminal cases that have caught the attention of the public over the decades, and this has not always had positive ramifications for the field of DNA analysis. As in any type of profiling, there is more art to it than science, some DNA analysts view the field as something that should be used in a role that is more supportive of investigative police work and not relied upon as a main source of evidence. DNA analysis is not yet completely exact, nor does it offer exact methods of identification, considering the fact that it still has a relatively small database and not everyone’s DNA is on record. Were everyone to contribute to a DNA database and allow a DNA profile to be constructed, the use of DNA analysis in the gaining of evidence would likely be much more palatable.

How DNA Analysis is Used Today

Today, DNA analysis is a helpful indicator—a clue—that investigators can use to help reconstruct the scene of a crime. While DNA analysis has its uses in some cases, such as where an accused may attempt to prove his or her innocence through DNA evidence (or lack thereof), there are plenty of instances in which DNA evidence can be manipulated or faked or even completely misunderstood (Austin, 2015; Worth, 2018). The limitations of DNA analysis, however, do not prevent its applicability in the criminal investigation process, as a case from 2002 in Europe shows.

In 2002, woman in Berlin was attacked in her apartment building and nearly killed. The medical community was able to save her life and the story she told to investigators about her attack included a single man, who entered her room and attacked her. Blood was found on the glass used to smash the woman’s skull as well as on two towels and a baseball cap. The tenant next door was first suspected as the DNA that was analyzed revealed a DNA pattern that was consistent with his own. However, the tenant had not actually been in town at the time of the attack and had a solid alibi. So suspicion fell to one of the two other men who were staying in his flat at the time. They were related, moreover, and the police used haplotyping to obtain more information about the suspect. Haplotyping in DNA analysis was able to show that…