Personal Injury Lawyers and Experts

Personal Injury Lawyers and Experts

Personal injury lawyers who try cases understand the importance of expert witnesses. A good expert can dramatically improve an accident case. The other side of the expert witness coin is that a bad expert can be equally disastrous. It is critical that personal injury lawyers who do jury trials know how to assess and correctly utilize expert witnesses. Personal injury cases in Las Vegas are frequently won or lost based upon the effectiveness of an expert. The best personal injury lawyers understand that the right expert can teach the jury to understand any complexities that may exist in the plaintiff’s case, and more importantly, can persuade the jury to accept the plaintiff’s version of the case.

What is an Expert Witness?

Simply put, an expert witness is a person whose specialized knowledge will help the jury decide the case correctly. Properly used, personal injury lawyers use expert testimony to provide a jury that is required to resolve a complex factual or technical issue with an opinion about inferences which should be drawn from the evidence presented in the case that the jury might otherwise find difficult to interpret accurately. The Nevada laws pertaining to experts track the federal law that governs expert witnesses in many ways. Therefore, Nevada courts give great deference to federal cases construing expert testimony when they are required to resolve a legal issue involving an expert.

What does Nevada law require before a jury can hear expert testimony?

Before a witness is allowed to testify as an expert, the judge presiding over the case must make a number of inquiries to determine first, does the person qualify as an expert and does the expected testimony assist the trier of fact? Additional considerations exist, but primarily, the two foregoing issues constitute the bulk of the analysis and the majority of expert witness related litigation. Because of the overwhelming use of experts in personal injury cases, it is particularly important that personal injury lawyers be well versed in the fundamentals of admitting and utilizing expert testimony.

Qualification Requirement

The initial determination that must be made when deciding whether someone may testify as an expert witness in Nevada is whether he or she is qualified in an area of “scientific, technical, or other specialized knowledge.” The factors a judge may consider in determining the extent of a potential expert witness’ knowledge are not exhaustive but include the following: academic background, licensure, employment experience, practical experience, and specialized training. The factors may be afforded varying weights and are often not equally applicable in every case. The important thing is that the judge, after careful consideration of the relevant factors, finds a substantial basis to declare that a witness qualifies as an expert. In Las Vegas, experienced personal injury lawyers understand that it should not be taken for granted that the trial judge will automatically declare a witness an expert. It is incumbent upon trial counsel to thoroughly prepare and be ready to convince the trial judge deciding the issue that the witness is in fact abundantly qualified to testify as an expert. All too often, underprepared personal injury lawyers who have minimal experience in the courtroom make the mistake of assuming their expert qualified and then find themselves in the unenviable position of not being able to present critical expert testimony at trial.

Assistance Requirement

Just because the court determines that a witness has sufficient expertise to qualify as an expert does not mean he may now testify at trial. The court must also find that in addition to the witness qualifying as one who has sufficient expertise or knowledge, the witness must also be able to “assist the trier of fact in understanding the evidence or determining a fact in issue.” The assistance requirement requires the court to consider a number of very specific issues that must be decided in favor of the expert in order for him or her to testify. The law in Nevada holds that the assistance prong is only satisfied when the trial judge finds that the two component elements of the assistance prong – relevance and reliable methodology are sufficiently proven.


Once the court deems the expert qualified in the sense of having sufficient expertise, the next hurdle requires personal injury lawyers to establish that the expert testimony they seek to introduce into evidence at trial is relevant to the case. Relevant evidence is any evidence that has any tendency to make a fact more or less probable than it would be without the evidence. To be relevant, the evidence must also be of consequence in determining the action. Think of relevance in the following terms: first, the evidence must make a factual proposition more or less likely than it would be without the evidence; and second, the evidence must be material – there must be a link between the factual proposition and the underlying law of the case. Simply put, relevance seeks to allow only those facts important to the controversy into evidence. Juries should not be subjected to meaningless information. They should only be asked to consider facts that are germane to the resolution of the dispute before them.

Reliable Methodology

The final hurdle requires personal injury lawyers to show that the expert testimony is the product of a reliable methodology. In order to satisfy this element, personal injury lawyers need to show a number of factors. First, the judge must be persuaded that the expert’s opinion is within a recognized field of expertise. The second factor requires that a showing is made that the subject matter underlying the opinion is testable. The third factor to be considered is that the conceptual matter underlying the opinion has been subjected to publication and peer review. Additionally, the subject matter of the opinion must be generally accepted in the scientific community. Finally, the opinion must be based on “particular facts rather than assumption, conjecture, or generalization.”  It is important to note that Nevada law holds that the factors are not exhaustive and may be accorded varying weights and that not all factors will apply in every case. The important thing is that the district court judge thoroughly considers and evaluate the factors that are applicable to the case and make sure that the expert will assist the trier of fact by rendering an opinion based on scientific and logical criteria, not the result of speculation, conjecture, or pseudoscientific research. Clearly, given the prevalence of expert witnesses in tort litigation, it is especially important that personal injury lawyers become highly proficient in applying these factors.

Common Expert Issues in Personal Injury Cases

Personal injury trials almost always involve medical expert testimony. Different standards apply to medical expert testimony depending upon the purpose of the testimony. Frequently, personal injury lawyers will use expert testimony to establish causation. Causation, for legal purposes, is the causal relationship between conduct and result. Generally, causation for personal injury purposes connects the careless conduct of the defendant to the injury suffered by the plaintiff. When medical testimony is offered to establish this critical element of the tort of negligence, it “must be stated to a reasonable degree of medical probability.”  Therefore, when medical testimony is stated to a reasonable degree of medical probability, the medical expert is stating his or her opinion based on at least a 51% probability, or in other words, by a preponderance of the evidence. This type of expert testimony is inherent to almost any plaintiff’s case.

Alternatively, if the defense seeks to contradict the plaintiff’s medical causation theory, the defense expert need not state alternative causation theories to a medical degree of probability. The Nevada Supreme Court has held that so long as the defenses of alternative medical causation are “competent and support by relevant evidence or research,” they need to be stated as more likely than not. However, this entirely depends upon whether the defense expert takes the plaintiff’s medical causation theory into account. If the defense expert does not take the plaintiff’s theory into account, he or she must adhere to the medical degree of probability standard.

Additionally, the defense will frequently seek to admit evidence of a prior injury or preexisting condition in order to eliminate or lessen their liability to the plaintiff. Nevada law holds that “unless it is readily apparent to a layperson,” a defendant seeking to introduce evidence of a prior injury must produce an expert who can demonstrate the relationship between the prior injury and a fact of consequence in the case. The defense cannot simply assert a prior injury; they must be able to make a showing by competent evidence that a causal connection exists between the prior injury and the injury at issue in the case.


The personal injury lawyers at Oronoz and Ericsson Injury Lawyers have significant experience working with expert witnesses. We utilize expert witnesses both as case consultants and trial witnesses. Correctly using an expert witness in a case can be difficult. It requires a fundamental understanding of the law as it relates to experts. There are various standards that must be mastered as well as issues pertaining to expert selection and witness preparation. Some experts are absolutely brilliant individuals, but they make terrible witnesses because they cannot adequately reduce their opinions to a level most jurors can understand. Other experts make poor trial witnesses for other reasons. That’s why it is essential to carefully select the appropriate expert for each individual case. It is not a one-size-fits-all endeavor. Much thought and consideration needs to go into making the choice of which expert witness will be a good fit for a given case. The personal injury lawyers at Oronoz and Ericsson Injury Lawyers understand these issues and look forward to using their expertise on your behalf in the event that you need representation for a personal injury matter in the Las Vegas area. If you or a loved one is injured as the result of someone’s carelessness in Southern Nevada, call the personal injury lawyers at Oronoz and Ericsson Injury Lawyers. We can help.

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