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Field of Expertise of an Expert Witness - How to Establish

     By HG.org

The field of expertise is important for any testifying witness, but it is crucial to ensure the reliability of the subject matter from an expert witness that will testify about the subject in his or her background. To ensure that the reliability exists, there are certain qualifications that the professional must present and an interview he or she must pass.
The field of expertise in a case relies heavily on the professional attached to the subject matter. His or her reliability in the claim or case may depend on his or her credentials and background. If the professional fails to qualify to remain in the case, his or her reliability failed to pass the necessary tests. Establishing the reliability is important, and it may ensure that the information supplied by the professional is the best possible for the judge or jury. Many of these situations call into question the knowledge, skill, capability, training and education of the professional in how he or she will form opinions and present them in the courtroom.

Reliability through Scientific Facts or Data

Many experts must explain a matter that has a foundation in scientific, technical or a specialized knowledge that the professional possesses. Then, he or she may provide reliable information to the judge or jury panel through his or her testimony that has a basis on facts or data. He or she may need to test evidence or use proven methods that pose no greater error rating than five percent. Any higher rating of failure or error in testing evidence will skew data and cause results to become variable. Then, the basis of testimony is false and the details the professional gives to the courtroom are not sufficiently based on fact or data.

Relevance of the Subject Matter

The field of expertise of the expert requires relevance to the case. It must contain reliable testing data and methods, but without a relevance to the case, the results may not matter. Some cases are unable to proceed if the testimony has little relevance to the subject material. If the victim in a civil suit is suing an insurance company that refuses to provide a settlement, the expert witness may need to provide a detailed explanation of the evidence at the scene. If he or she does not work in vehicles, accidents or crime scenes but botany, he or she may not provide a reliable explanation of what happened due to a lack of relevance.

Intelligent Evaluation

The expert in the case must have the ability to assess the evidence and provide an intelligent evaluation of the specifics. This generally refers to a scientific, technical or specialized knowledge or expertise of the professional in some manner to give the courtroom testimony about the incident or evidence with any confidence. If the professional does not understand the materials or how they connect, he or she may only guess at the results or how the testing outcomes associate to the scene of the crime or incident. Additionally, if this person is unable to evaluate the testing results in an intelligent manner, he or she may not remain reliable in this field of expertise to the courtroom.

Reliability in Exposition of Scientific Principles

When an expert witness or another expert must testify in the courtroom, it is possible to establish reliability by what the person presents to the courtroom. He or she may use the exposition of principles that follow a certain scientific or technical path. This could explain certain issues based on already established theories or lines of thought by other experts and professionals from years past. The exposition will often contain facts and data from others that supply a theory or known quantity. Sometimes this applies to testing, but in other situations, the testimony relates to the evidence or scene of the crime.

The reliability increases significantly if the expert uses other facts and principles to boost his or her testing or testimony. This demonstrates to the judge that his or her opinion and conclusion of the subject matter has a foundation built on fact and other professionals. However, the discretion of the judge still stands to qualify the expert based on this path.

The Reliability of the Expert

By establishing the reliability of the field that the expert follows, it is possible to see the expertise he or she has based on knowledge and skills. The use of testing methods and reliance on other professionals increases the strength of reliability.

Copyright HG.org


While every effort has been made to ensure the accuracy of this publication, it is not intended to provide legal advice as individual situations will differ and should be discussed with an expert and/or lawyer.

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