Abstract
The present paper has used DNA and insider trading cases to illuminate important concepts associated with the use of expert testimony in a court of law. From the analysis of the cases, the paper has been able to synthesis most of the principles that guide the use of expert testimony. Additionally, the paper has dwelt on the functions of an expert witness and methodological issues that dictate the use of expert testimony.
Many courts use scientifically sound and impartial expert witness testimony to assist in settling disputes that occur in everyday life events. By definition, expert testimony in forensic psychology contexts denotes the evidence about a particular scientific, technical, or professional issue provided by an individual who is suitably competent to testify based on factors such as familiarity with the problem, special training in the specific field associated with the issue, and prior experience (Fulero & Wrightsman, 2009; Sapir, 2007). This paper uses two cases to illuminate important concepts associated with the use of expert testimony in a court of law.
Analysis of Cases
In United States v. Richardson‘s case (537 F.3d 951), the 8th U.S. Circuit Court of Appeals ruled that it is appropriate to admit the testimony of an expert witness who based her DNA evidence on a peer review of the DNA tests, meaning that she was not directly involved in conducting the actual tests. In admitting the evidence, the judges ruled that the testimony of the DNA expert neither contravened the Confrontation Clause nor constituted hearsay (Ambrogi, 2008).
This case identifies the concepts of expert opinion, actual experience, and sufficiency of facts in expert witnesses. It can be argued that the judges admitted the evidence despite the challenges of using a peer review due to the fact that the DNA professional was scientifically and technically qualified to provide expert opinion on the issue (Ramos, Callier, Swann, & Harvey, 2016).
Additionally, owing to her experience and specialized knowledge on DNA issues, the judges were able to rule that her evidence could not have been based on hearsay. The hearsay element is a clear pointer to the fact that expert testimonies must always be based on scientific, technical, or other specialized competencies (Fulero & Wrightsman, 2009).
The Richardson case also illuminates the component of grounding the expert testimony on reliable principles, standards, and methods (Fulero & Wrightsman, 2009). It is evident that, although the expert in the case did not conduct the actual DNA tests, the evidence produced in court was based on a peer review of the DNA tests that were based on reliable principles and methods. Such an orientation demands that the testimony must be grounded on sufficient facts or data for admission in a court of law (Houston, Hope, Memon, & Don Read, 2013).
However, it is important to note that the law allows lay people to provide subjective opinions based on their own perception in a process that cannot pass the strict tenets of expert witnesses. The case rightly demonstrates that expert testimonies must be provided by individuals with the right educational background, experience, training, and skills that allow them to develop accurate opinions and draw correct conclusions on a particular issue.
It is important to develop an adequate understanding of the functions of an expert witness so that the methodological dynamics associated with the use of expert testimony are illuminated. In the United States v. Nacchio case (519 F.3d 1140), the 10th U.S. Circuit Court of Appeals found that Joseph Nacchio was wrongly convicted on 19 accusations of insider trading due to the exclusion of an expert witness who failed to divulge the methodology used to arrive at his opinions when giving evidence in the trial court (Ambrogi, 2008).
This case laid bare the confusion existing in the functions of an expert witness and the methodology for disclosure of expert testimony in criminal and civil proceedings. Available literature demonstrates that the expert witness undertakes two principal functions, namely:
- the scientific function – collecting, testing, and evaluating evidence and forming an opinion as to that evidence;
- the forensic function – communicating that opinion and its basis to the judge and jury” (Sapir, 2007, p.1).
It is evident from the case that Nacchio was wrongly convicted by the lower court due to a misunderstanding of the forensic function of the expert witness. The available literature is consistent that, while the rules of civil proceedings require expert witnesses to prepare and disclose a comprehensive report, the criminal legal procedures do not require an in-depth discussion of the methodology used by expert witnesses to make opinions (Houston et al., 2013).
Consequently, the Supreme Court found that the exclusion of the expert witness on the ground of failing to disclose the methodology used to make an informed opinion was a misuse of discretion (Ambrogi, 2008). The implication of this case is that legal systems need to understand the functions of an expert witness and how these roles are used in court to give evidence.
Conclusion
This paper has used two cases to illuminate several concepts associated with the use of expert testimony in a court of law. The concepts of expert testimony discussed in the paper include expert opinion, actual experience, educational background and skill, the sufficiency of facts, reliability of principles and standards, as well as definitional and methodological issues. From the discussion and analysis of the cases, it is clear that expert testimony is a fundamental component of law enforcement, criminal justice, and other domains that require the use of forensic psychology.
References
Ambrogi, R. (2008). Top 10 expert witness cases of 2008. Web.
Fulero, S.M., & Wrightsman, L.S. (2009). Forensic psychology (3rd ed.). Belmont, CA: Cengage Learning.
Houston, K.A., Hope, L., Memon, A., & Don Read, J. (2013). Expert testimony on eyewitness evidence: In search of commonsense. Behavioral Science & the Law, 31, 637-651. Web.
Ramos, E., Callier, S.L., Swann, P.B., & Harvey, H.H. (2016). Genomic test results and the courtroom: The roles of experts and expert testimony. Journal of Law, Medicine & Ethics, 44(1), 205-215. Web.
Sapir, G.I. (2007). Qualifying the expert witness: A practical voir dire. Forensic Magazine. Web.