Accuracy of DNA Printing

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Accuracyof DNA Printing


Introduction 3

Historical Background 4

Opposing Arguments 6

Ethical Issues 8

Conclusion 11

References 13

Accuracyof DNA Fingerprinting


Theterm DNA for most people today has them thinking about a televisionprogram they have seen and how criminals have been convicted based onDNA evidence or a family union that happened following similar DNAsamples. It is no longer a new thing in that more people are awarewithout knowing it about the practice of DNA fingerprinting just bysitting in the comfort of their homes (Green, 2014). What a majoritydo not know is when fingerprinting started being used and how it hasgrown over the years, the numerous opposing views about its use, andthe ethical concerns that have continuously been raised regarding itsuse. For many, these issues become important once the need to use thetool comes up or when arrested and DNA samples are collected.

Thebreakthrough in solving crime that came with the discovery of DNAfingerprinting is irrefutable with so many major cases, particularlymurder mysteries and rape, being solved through DNA-based evidence.The identification of individuals through their unique DNA sequencehas not only led to case solutions but also helped reunite familiesand enable others to bury their loved ones after body scathingaccidents (Green, 2014). The breakthrough has led to the widespreadcreation of databases that contain DNA information, which has servedto help the system convict those held faster than ever before.However, despite the clear achievements of this approach to solvingcrime, a number of people have criticized it for exposing people topossible future threats, a factor that has raised ethical concernsabout the use of DNA fingerprinting (Burney &amp Pemberton, 2016).

Thispaper shall focus on DNA fingerprinting and its application in themodern world, particularly in the criminal justice system. To achievethis, it shall discuss the historical background of DNAfingerprinting from its introduction to its use to date, the opposingviews that have been posed regarding the use of fingerprinting, andfinally the ethical issues that surround the tool. The discussionpoints are divided into subheadings separating the differentarguments from each other.


Commonlyknown as DNA testing, this approach to identifying individuals iscommonly used in forensics to identify a person based on thecharacteristics of their DNA. The name fingerprinting comes from thefact that this method, like fingerprint profiling, manages to detectdifference between individuals since every single person has uniquegenetic makeup similar to unique fingerprints. The form ofidentification has been rated as one of the greatest discoveries fromthe 20thcentury due to the impact it has had in improving pathologicalinvestigations (Burney &amp Pemberton, 2016). Since itsintroduction, there have been breakthroughs in cases involvingidentification of criminals, victims of disasters, crimes, and war,and parental origin.

Theorigin of DNA fingerprinting is credited to Alec Jeffreys of 1984,who was working at the University of Leicester where during his testson DNA, found that it elicited unusual variable and hereditablepatterns following several locus analyses (Burney &amp Pemberton,2016). His work was mainly centered in heredity factors in families,and his tests on DNA revealed that every human had repetitivearrangements of DNA, which varied in length per person. The patternsare known as Variable Number of Tandem Repeats (VNTR) and as hediscovered could be used to uniquely isolate a person (Burney &ampPemberton, 2016).

Followingthe discovery, the use of DNA fingerprinting as Alec called itextended across biological studies especially in the study ofdiversity and conservation of species. The impact of the discoverywas, however, felt following its application to solve both criminaland civil cases through pathological genetic profiling where resultswere used as evidence in court cases. Forensic fingerprinting wasfound applicable in the cases since it serves to compare the DNA fromindividual’s nucleated cells with any organic matter found at thesight of crime or with another person’s DNA for the purpose ofisolation (Burney &amp Pemberton, 2016). Through it, many innocentpeople who would have ended up in jail have been exonerated whilethose found guilty have been incarcerated for their crimes.

Furthermore,since its introduction, the cases solved using DNA fingerprintinghave been those that could have otherwise gone unsolved as shown bythe example of the 1987 forensic cases of rape. In the two scenarios,there two girls raped and murdered in different occasions where semenobtained from the scenes of crime was used to exclude the suspectedman while at the same time find a match with the man who laterconfessed to the crime (Burney &amp Pemberton, 2016). The remarkablesuccess of the approach led to the expansion of its use worldwidewith more organizations employing it in their work which in turn ledto expansion of studies on how to improve what was already beenapplied.

Moreover,the widespread use of DNA evidence in court cases continued for yearsuntil the 1990s where some attorneys began challenging theacceptability of DNA tests which led to increased research and changeof method from what was first introduced by Jeffreys. Reliability ofthe results given by DNA tests was mainly based on validity oftechniques used to derive and deduce the results and on thetrustworthiness of the labs or specialists involved (Green, 2014).The replacement of the original method of testing that usedrestriction length fragment polymorphisms (RLFP), VNTR loci withpolymerase chain reaction (PCR), and sequencing through the use ofshort tandem repeats (STR) evoked further questions about reliability(Burney &amp Pemberton, 2016). Through the 2000s, there were morecases questioning reliability of DNA fingerprinting results which ledto the joint agreement that the issue would stop been brought up incourt unless there was substantial evidence.

Toensure that all results given by DNA test results were reliable theUS federal government through the Federal Bureau of Investigation(FBI), created Combined DNA System commonly known as CODIS (Green,2014). Through the system, all laboratories that carry out forensictests were mandated to ensure that the methods used werecomprehensive and binding which eliminated the wide spread cause forconcern about DNA evidence. With all states having the CODISdatabase, DNA information has been made present across the statesespecially with most states requiring DNA specimens from allconvicted felons (Burney &amp Pemberton, 2016).

Todate, the use of DNA profiling continues with improvements being madeto ensure that it is reliable in all circumstances. The widespreaduse has not only led to solutions for the most complex cases orexonerating innocent people who had been guiltily charged but intoother biological fields as well. Today, it is common for familyissues involving paternity identity to be solved through the use ofDNA tests, which has in turn worn many illegitimate children rightsof care from their biological parents who may be absent (Green,2014). Additionally, DNA test results have helped identify relativeswho may have been involved in war crimes, accidents, terror crimesand other tragedies that may have left them scared beyond physicalrecognition (Burne &amp Pemberton, 2016). It is through the resultsthat families of the dead have managed to establish whether those inthe accident are related to them which have in turn reduced thenumber of unidentified bodies in the morgues. It is through theseother applications that the true intention of Jeffery in studying DNAis truly realized despite the deviation from the original method ofsequencing.


Thepopularity of DNA fingerprinting has been established by the numberof breakthroughs it has brought no only in court cases but in thebiological field. However, like every other popular scientificdiscovery, DNA profiling has been met with opposing views,particularly from those who question its credibility. One of the mostpopular opposing views about DBA fingerprinting is its use asevidence in court cases, particularly those that involve murder.Majority of the opposition have pointed out that the notion of DNAevidence been uncontestable has also led to conviction of innocentindividuals. Take for example a case discussed by Langley (2012), inthe Telegraph where a man who relies on an oxygen tank is accused ofthe murder of a sex worker based of his DNA been found in thefingerprints of the victim. According to the prosecution, the DNAcould only be present since the victim was trying to fight off theaccused (Langley, 2012). This is not the first case where the onlyevidence has been based on DNA as further pointed out by a case of ayoung woman from Italy been acquitted as a suspect in the murder ofher roommate.

Thecases presented above have helped oppose the use of DNAfingerprinting, especially in court cases, since there could clearlybe more logical explanations for the presence of the accused person’sDNA in the crime scene. Langley (2012) for example points out thatthe accused has a skin condition that causes flaking, which meansthat his skin cells could have been in the car or on something hetouched consequently transferring to the victim’s fingernails. Thecredibility of DNA evidence is hence brought to question in suchcases especially since law enforcement officers have taken to makingit a shortcut to finding the most likely person to convict for thecrime (Green, 2014). The need to reduce the amount of importanceplaced on DNA evidence remains since this argument points out to agap that needs to be filled in order for all people to feel thatjustice has been served for all.

Theopposition against the use of DNA fingerprinting has also been basedon evidence that DNA could be contaminated which has led to wrongfulconviction of some accused criminals (Murphy,2013).Though most governments across the world have established data baseswith samples from felons the issue of accuracy remains due tocircumstances where handling of samples has led to contamination ofevidence. It is through this opposition that initiatives, such as theInnocence Project have been created with most members having criticalviews about crime laboratory techniques (Murphy,2013).Contamination in most cases has been based on cross-contaminationwhere two types of DNA, that of the accused and the victim, may havebeen placed together meaning that evidence collected from the samplesis likely to lead to a guilty charge for the accused. An example isgiven by Ewanation,Yamamoto, Monnink, and Maeder (2017) intheir overview about DNA technology and crime about how DNA from anunknown woman was found in various crime scenes around Europe linkingher to crimes that were unrelated. It was later established that theDNA was not part of the crime scenes but rather in the cotton woolthat was used to collect samples from the scenes of crime (Ewanationet al., 2017).The gauzes of cotton used, though sanitary, were not qualified tocollect genetic material and their use made it impossible to isolatefalse evidence from real.

Theconsequence of contaminated DNA samples has led to conviction ofinnocent people especially in cases where the prosecution choses tofocus on one set of DNA which may be the false lead. Potential errorsin the laboratories can also lead to accusation of the wrong personswhere in this case the federal regulations given to every operatingforensic lab seek to eradicate in a bid to reduce the amount of doubtplaced on DNA evidence presented in courts (Langley, 2012). It isestimated that some cases that are considered cold cases where DNAevidence collected belongs to a felon already in the database may endup in conviction of innocent people despite having criminal records,especially in cases where they are linked closely to the victim.Further arguments against fingerprinting are as a result of the manyethical concerns raised regarding its use especially by governmentagencies despite the clear success in solving criminal and civilcases (Langley, 2012). The issues discussed in the following sectionof ethical issues portray further points of opposition against thishighly acclaimed tool.


Scientificinventions, particularly those that involve genetic testing, raisenumerous issues regarding their use in human health and socialpolicies and how the results gained should be applied. The majorquestion that causes wide public uproar is whether people should begiven the chance to choose whether to take the test or not and whohas access to the results once the tests are carried out. One of thehighly-criticized uses of genetic information gathered fromfingerprinting data has been through geographical and racial genetictesting used in criminal investigation to help reduce the search forsuspects (Lawless, 2013). Critics have any data gathered through thisapproach is likely to be used for research in future about therelationship between race and crime, with DNA evidence serving assolid proof for the claims. In such a case, the fingerprinting datacollected from a few members of a given ethnic group, could lead tothe total prejudice and scientific based discrimination against themwhich may in turn cause flaws within the judicial system (Lawless,2013).

Whileproponents of fingerprinting point out that having data on individualgenetic results has more merits, opponents point out that keepingthis data raises ethical concerns particularly on personal privacyand security. Unlike other forms of identification, such asfingerprints and facial recognition, genetic fingerprinting is moreintrusive to a person which means that acquisition of DNA data posesa threat to their privacy (Murphy, 2013). Government organizationssuch as the army have already created databases with geneticinformation on their members while the criminal justice system hasits own database with genetic datasets from any convicted felons inthe country. The question comes up about how safe this information isfrom future use by researchers or other interested parties and whatrepercussions it will have on people. Such questions have led to theoutrage against collection of DNA profiles from most peopleespecially use in past criminal cases and tracing people (Murphy,2013). For now, in response to such concerns and fears, the U.S.,France, Canadian and other governments have mandated that DNAfingerprinting database be kept only for judicial use, withadministration happening in legalized testing laboratories, thusensuring the safety of the information.

Withregard to the issue of databases that contain DNA fingerprintingdata, there have been cases where innocent people have been includedin the database, especially in the United Kingdom where the platformwas introduced in the 1990s leading to wrongful conviction ofinnocent persons (Ewanation et al., 2016). The essence of thedatabase initially was to have indefinite records of DNA informationfrom any individual who had been found guilty of a crime but ended upcontaining data from innocent people who were only suspects (Murphy,2013). According to Jeffreys, this practice has served to put boththe guilty and the innocent in one level, a factor that hasinterfered with the application of justice which eventually makes thedatabase counter-effective. It is such cases that have brought up theneed to ensure that the national databases created for judicialpurposes are separate from those created for the purpose of findinglost relatives and tracing parent origin (Ewanation et al., 2016).

Asmore countries seek to expand their DNA based databases in a bid towin the war against, the possibility of having everyone’s DNAprofile increases and so have the ethical and legal concerns aboutthe move. The rise of computer crimes and hacks into government datasystems, especially presents a strong case against this move since itis clear that the safety of this information lies in the hand oftechnology, which could be penetrated at any time. DNA is a tool thatin the wrong hands could lead to destructive results on targetedindividuals (Lawless, 2013). The move by the criminal justice systemin the US permitting police officers power to take swabs from anyarrested persons without a warrant means an increase in number ofinnocent people in the national database. The consequent inclusion ofthis data in the national databases, clues into a bleak future wherepersonal security may be compromised as the line between guilty andinnocent becomes blurred (Lawless, 2013).

Inthe United States, the issue of racial disparity and theconsequential discrimination of the black population have beencontinuously raised since the existing database has a high percentageof black men it. Critics cite this as an ethical issue since it hasalready been established that black men are unequally targeted in thecriminal justice system even in cases where there is no evidenceshowing that they are guilty. This means that in a given number ofarrests, more innocent black men are added to the database, puttingthem at risk of been convicted of a crime they did not commit infuture (Green, 2014). The database serves as a record for a crimewhich means that those released after been proven innocent end uphaving a record that marks them as criminals in future. Thisincreases the margin of black men trapped in the criminal justicesystem and further accelerates racial discrimination against blackpeople (Green, 2014). In light of this, there is need to regulate thelegislation allowing police to collect DNA samples to specificguidelines that limit the number of innocent people in the databaserelated to convicted felons.

Apartfrom DNA databases, there have been contentions regarding theretention of DNA samples which many police departments hold onto forlong periods raising concerns about the privacy of the owners. Insome countries, such as Germany, the samples are destroyed once theprofile is obtained as a measure to prevent them from been reanalyzedfor other personal information such as health of the individuals(Langley, 2012). In most cases, criminal based DNA profiles onlyrequire the identification aspect of DNA, however, presence ofsamples means that they are exposed to further analysis which couldexpose health information of individuals which is a breach of privacyunless during medical tests which are often done with consent(Langley, 2012). There is therefore need to ensure that in all casessamples are destroyed once they serve their purpose in each givencase.


Theachievements of DNA sequencing, particularly in solving both criminaland civil cases, remain undisputed, which is why efforts to ensurethe efficiency of its use should be continuously supported especiallyin the war against terrorism. However, the use of databases thatcontain DNA profiles of individuals should be created more carefullyto ensure that no innocent person is profiled along with the guiltysince this defeats the purpose of creating it. It advisable that DNAinformation and samples collected from those who are exonerated andthose who are innocent be deleted upon their release, use or includedin a separate database for fingerprinting to be successful and forreduction of racial disparities. Additionally, the systems should bewell guarded from external intrusion for the privacy of those addedto it from malicious use that may result to serious problems.


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Ewanation,L. A., Yamamoto, S., Monnink, J., &amp Maeder, E. M. (2017).Perceived realism and the CSI-effect.&nbspCogentSocial Sciences,&nbsp3(1),1294446. Retrieved from

Green,M. (2014). With liberty and justice for all: The costs and benefitsof DNA databases. Retrievedfrom

Langley,W. (2012). The case against DNA. Telegraph,UK.Retrieved from

Lawless,J. (2013). Spread of DNA database sparks ethical concerns. PhilstarGlobal.Retrieved from

Murphy,E. (2013). License, registration, cheek swab: DNA testing and thedivided court. Retrieved from