Forensic Science and Contextual Bias

This assignment delves into the critical issue of contextual bias in forensic science. It examines how unintentional or even deliberate biases stemming from preconceived notions, beliefs, and cultural values can affect the interpretation and presentation of forensic evidence. The discussion highlights specific case examples where bias has led to errors, such as the Brandon Mayfield, Cowans, and Mackie cases. Strategies for mitigating bias, including blind testing and proficiency tests, are also explored to emphasize the importance of objectivity in forensic investigations.

Running head: FORENSIC
Forensic
Name of the Student:
Name of the University:
Authors Note:

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Table of Contents
INTRODUCTION:..........................................................................................................................3
CONTEXTUAL BIAS:...................................................................................................................3
CASE EXAMPLE:..........................................................................................................................4
OPTIONS IN FORENSIC EVIDENCES:.......................................................................................6
Conclusion:......................................................................................................................................7
Reference.........................................................................................................................................9

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INTRODUCTION:
The Forensic science mostly deals with the examination that are performed in public by
the experts. It is closely tied with scientific methods that is used in solving crime cases. Now
days it has become essential part of the judicial system. As when cases arrives related to life and
death, forensic evidences plays a crucial role. Here key evidence in criminal cases may have
come from witness or other subjective means from the past, but forensic always relies on
objective evidences (Dror et al. 2013). In the judicial system, accuses remains innocent until
proven guilty by the evidences and law. Thus, both the defense and prosecution in many court
cases now regularly use it.
CONTEXTUAL BIAS:
The recent analysis on contextual bias has discovered that the examiner’s subjective
decision and observation can be misled by excessive information and influences. As experts are
intentionally taking vulnerable and erroneous decision after getting touched with the influential
people. Thus the objectives are always tends to be hampered due to minor influences that leads
experts to develop expectation about the outcomes of the examination (Buckleton et al. 2016).
Thus, there is a biasness due to wishful thinking, self-fulfilling prophecies, traditional values and
belief perseverance. These biases work unconsciously without any wrongful intentions on an
examiner. Thus these factors are not deliberate or due to incompetence. However, these factors
are sincere and thus it affects dedicated forensic experts. These influences generally comes from
different sources. There is a major role of the investigator as the theory of the case are in charge
of him and at same time, his work is to provide information necessary and relatable to the
experiment. Example of biasness includes communication between the colleagues working on

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the same experiment may share their results from each other’s work or from the transmittal
letters that accompany evidences can induces a biasness in expecting the experiment outcome or
acts as tunnel view if the case contains irrelevant information regarding the experiment (Quick
and Choo 2014).
CASE EXAMPLE:
Case 1: BRANDON MAYFIELD CASE –
There are many examples of contextual bias in forensics that occurred in recent times. A
case related to Brandon Mayfield is an example of contextual bias. A bombing case occurred in
the year 2004 where erroneous latent fingerprinting identification was undertaken. The United
State Federal Bureau took the charge of investigation after Spanish police gave the necessary
information related to case like dormant fingerprinting found from the plastic bag. The FBI
surely identified Brandon Mayfield, as the criminal was a bomber. This experiment of
identification was further clearly justified by the finger printing experts and other FBI agents that
was appointed by the court itself. The methods of identifying the criminal was false due to
erroneous fingerprinting of the individual and was not due to methodology or technology
(O'Leary et al. 2015). It was a high profile case and there was a pressure to solve the case. The
primary examiner in matching more characteristics between the prints influenced the case.
Subsequent examination was then performed, as the initial result was not withheld during
verification stage, as the first examiner was highly respected supervisor. Error also occurred due
to overconfidence in being one of the best fingerprinting agencies and urgency of case was also
the cause that is related to the knowledge of the suspect’s spiritual belief and terrorist
association. From the above example, it is clearly understood environmental influences can bias
results for human hair examination. As criteria for identification of individualism occurs via

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methodology that is analysis, comparisons, evaluations, verifications. In this case first from of
analysis was done based on the fingerprints found at the site of the investigation thus errors took
place how contextual bias works. From the experimental study it was clear that as fingerprinting
experts came to a decisions from the information provided by the police and critically analyzing
it in first form of methods and no other forms of methods were further followed (Coulthard et al.
2016).
Case 2: STEPHAN COWANS CASE –
Another example of contextual bias is the case of Stephan Cowans who become
suspected as his name was suggested as someone who sold a hat to a criminal. This may have
initially biased the investigation purposes, as it was an extraneous influence all around. Later
print was found at home were of perpetrators daughter and mother that was misattributed to
Cowans. As cows name was wrongly appeared. After those six years have passed, DNA
evidences later rectified Cowans. There was another error committed by the fingerprinting
examiner who had done mistake but proceed in the experiment through trail (Ward 2015). In this
experiment, results came from the analysis of latent print by observing only the seller who was
assumed to be suspected in this case. Later the seller was not found guilty as other processes of
comparisons prints were done that passed the final review process, as peer review process was
apart that checks the procedure that took place during the experiment.
Case 3: SHIRLEY MACKIE CASE –
SHIRLEY Mackie case was also an example of contextual bias. Shirley Mackie was
detective constable who was arrested in the accusation of falsehood for stating under oath as a
crown witness. There a fingerprint was found in the crime scene of murder that was not her

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prints in that case. The finger printing experts proved this evidence of fingerprinting. Later the
result was found to be erroneous. Here in this case the fingerprints were found very similar to the
suspects so the experts concluded a positive identification when enough similar characteristics
were found. This change in fingerprints may have occurs due to skin disease or with contact of
other substances that leaves pattern ridge impression on the surface of the skin (Kukucka and
Kassin 2014).
OPTIONS IN FORENSIC EVIDENCES:
The Options are considered those measures that are undertaken in order to counter effect
the contextual bias. Different aspects of options have been discussed in brief in the later part of
the report.
Types of Options and their relevance:
Blind Testing:
Blind Testing is the simplest form of options in forensic science which are used in order to
counteract the contextual bias. Here no irrelevant information are given to the experts so that
they cannot be influenced by the details. Only necessary information are provided regarding the
case during the experiment. It sometimes occurs that important facts are required for execution
of examination thus it becomes exposed. Sometimes cases are revealed in order to get the
information so that task can be performed (Menaker et al. 2016). However, it requires filter
system of information. Sometimes officers removes suggestive domain irrelevant information
and form submission and they will help to coordinate the examination. At the time of experiment
the beliefs, expectation of police and other personnel are being guarded from the examiner.
Blindness to the context will ensure examiner based on the results on actual evidences.

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Double Blind Proficiency Test:
Another example is double blind proficiency test which is used to check the quality of
performance of forensic laboratory and also assesses the competence of the examiner. Here the
both the examiner and the laboratory are being unaware that their performance are being tested.
A series of unknown samples that are also unknown to the laboratory and examiner are being
sent for the examination. However, it gives a clear indications of the performance of an examiner
and his expertise.
Legal importance:
Forensic evidences is challenging based on contextual and conformation bias as it will appear in
Australian court for justification. In these course of experiment there is diversity in literature and
experimental studies as both varies in this regards. Despite of this, flaws courts still relies on the
forensic science and has faith upon it (Drake and Adams 2015). It also becomes a challenge to
the erroneous results because of extraneous influences that also becomes comprehended ideas to
the forensic science. However, it is not uncertain that forensic experts performs an invariable role
to the judge or jury. The judge and jury always provides interference regarding the experiment
results but it is also agreed that forensic cannot be held only responsible for erroneous results
(Vera-Rodriguez et al. 2017).
Conclusion:
In order to conclude the above discussion in brief it can be said that forensic is that
branch of science which deals with investigation of criminal cases. It is an integral portion of our
legal system. In recent times, forensic evidences have witnessed quite a few contextual biases
that might be unintentional or even intentionally. As it is seen in the above discussion that these

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bias operate unconsciously and the major elements of these are proved to be prophecies, beliefs,
traditional values, etc. These bias deviate the overall outcome of the forensic evidences. As the
important cases were discussed which were the cases of Brandon Mayfield, Cowans and Mackie
where it was observed that error took place due to biasness, overconfidence and negligibility. In
order to overcome these issue certain steps are needed to be undertaken. In relation to the
measures that are to be taken in order to overcome these problem the concept of options was
discussed which explained several methods that are used to counter effect these biasness. These
options include measures like Bling Testing, Double Blind Proficiency Test, etc. which act
toward taking corrective decision in the event of any biasness. It was also observed in the
discussion that these forensic evidences are always challenging based on contextual biasness.
However, it can be stated that the role of forensic science to jury or judge is always incomparable
and uniform.

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Reference
Buckleton, J.S., Bright, J.A. and Taylor, D. eds., 2016. Forensic DNA evidence interpretation.
CRC press.
Coulthard, M., Johnson, A. and Wright, D., 2016. An introduction to forensic linguistics:
Language in evidence. Routledge.
Drake, S.A. and Adams, N.L., 2015. Three Forensic Nursing Science Simulations. Clinical
Simulation in Nursing, 11(3), pp.194-198.
Dror, I.E., Kassin, S.M. and Kukucka, J., 2013. New application of psychology to law:
improving forensic evidence and expert witness contributions. Journal of Applied Research in
Memory and Cognition, 2(1), pp.78-81.
Kukucka, J. and Kassin, S.M., 2014. Do confessions taint perceptions of handwriting evidence?
An empirical test of the forensic confirmation bias. Law and Human Behavior, 38(3), p.256.
Menaker, T.A., Campbell, B.A. and Wells, W., 2016. Use of Forensic Evidence in Sexual
Assault Investigations: Perceptions of Sex Crimes Investigators. Violence Against Women.
O'Leary, A.E., Oberacher, H., Hall, S.E. and Mulligan, C.C., 2015. Combining a portable,
tandem mass spectrometer with automated library searching–an important step towards
streamlined, on-site identification of forensic evidence. Analytical Methods, 7(8), pp.3331-3339.
Quick, D. and Choo, K.K.R., 2014. Data reduction and data mining framework for digital
forensic evidence: storage, intelligence, review and archive.

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Vera-Rodriguez, R., Fierrez, J. and Ortega-Garcia, J., 2017. Dynamic Signatures as Forensic
Evidence: A New Expert Tool Including Population Statistics. In Handbook of Biometrics for
Forensic Science (pp. 329-349). Springer International Publishing.
Ward, T., 2015. An English Daubert? Law, forensic science and epistemic deference. The
Journal of Philosophy, Science & Law, 15(1), pp.26-36.