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When Is Expert Witness Testimony Admissible?

Ensuring that the testimony from an expert witness is admissible is of the utmost importance when the professional becomes part of the proceedings, and this is generally only possible if the expert passes the qualifications interview. Other rules regarding the admissibility of testimony exist and may apply depending on the type of case.

The primary concern with the admissibility of testimony for an expert witness is if the case involves a civil or criminal matter. In civil cases, the qualifications and standards are often lower than when the crime requires the justice system at work. The Federal Rules of Evidence apply for criminal cases that hold the admissibility of testimony and the expert to a higher caliber of guidelines. The testimony must have a valid basis or foundation on evidence, and it must clarify something to the courtroom or provide additional details that only the expert witness may present.

The Opinion Testimony of the Witness

For the expert to qualify as a designated expert witness for a case, he or she must pass the interview with the judge and opposing legal counsel. To do this, he or she must have a valid basis for his or her opinion. The witness perceptions of
testing and knowledge applied to the evidence are crucial. He or she must clear up a matter, provide new information that only a professional is able to provide and base his or her findings on scientific, technical or knowledge of a specialized subject. He or she must remain reliable in testimony and testing methods and have a relevance to the topic in the courtroom.

What Admissible Testimony Is

For an expert to ensure his or her testimony is admissible, he or she must follow certain guidelines. These generally include special knowledge or expertise in a certain matter. This often involves scientific, technical or specialized subject matter. The testimony itself must have a basis and foundation of facts or data that are sufficient to provide an opinion. If the expert is of a scientific background, his or her testing methods must remain reliable. The error rate must not exceed more than five percent such as due for any scientific testing of a professional in the field or in academics.

Reliable principles and methods generally apply to the testimony of an expert and are necessary for admissible testimony.
Applying similar methods to the facts and testing systems is important. The subject matter that the expert presents in the courtroom requires relevance. If he or she is not focusing on the specific matters of the case, he or she may face disqualification. It is possible to fail a Daubert challenge if the professional is not reliable in testing and relevant in the subject matter. However, the judge has a wide discretion in determining admissibility and examining the testimony and testing methods of the expert witness.

Admissibility of Testimony

The discretion of the judge is an important factor when the expert needs to confront all the factors. He or she needs to prepare beforehand and ensure that all materials are available. If he or she needs to create a report, the expert needs to know all the different elements and facets of the details. The testing methods are of particular interest and must remain reliable with an expected or dependable outcome. Consistency is important in testing evidence or else the results are either unclear or will not provide a stable conclusion. This could begin the disqualification process and lead to testimony becoming inadmissible.

The expert may need to explain to the judge how he or she determined the opinion that will help him or her present testimony in the courtroom. It must have a foundation in facts, data or the testing results. Putting these together, the expert may explain how to get from the beginning of the case to the conclusion through reliable tests and relevant subject matter. The professional must personally observe or become aware of the facts and data within the case. This provides a better understanding of the elements of the evidence and how it may connect to an opinion of what happened during the incident.

The Expert’s Presentation

The professional in a case will need to present his or her credentials, a report or qualifications to the judge. To ensure his or her testimony is admissible, he or she must pass the test. By remaining knowledgeable about the subject matter, understanding the relevance and using reliable and consistent testing, he or she may demonstrate his or her qualifications to the judge.

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Disclaimer: 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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