Experts are key witnesses in any case. They have the ability to testify about things that are usually beyond the scientific or technical understanding of the average person. If the expert is good at conveying that sort of information, it can have a big impact on how a jury resolves the case.
However, just because a person is listed on a witness list as an “expert”, doesn’t necessarily mean that that person will be allowed by the Court to testify as an expert. In Florida – like many states – the Court serves as a gatekeeper to ensure that a person being offered as an expert actually possesses specialized knowledge that will assist the jury in resolving a particular fact in dispute. Also, the Court will not allow a person to testify as an expert unless the person has taken certain steps required by law to form a proper expert opinion.
The Court’s gatekeeping role provides an opportunity for the opposing party to try to prevent the proposed expert from testifying if it can be shown that the proposed expert does not possess specialized knowledge or has not taken the steps required to form a proper expert opinion.
Here is a list of things that a litigant will need to show the Court to satisfy the Court that the person is suitable to testify as an expert (or – in the absence of – to prevent a person from testifying as an expert). First, the proposed expert must have scientific, technical, or other specialized knowledge that will assist the jury in understanding evidence or in determining a fact in dispute. Second, the proposed expert’s testimony must be based on sufficient facts or data.
Third, the proposed expert’s testimony must be the product of reliable principles and methods. Fourth, the proposed expert must have applied the reliable principles and methods to the facts of the case. It is the Court’s responsibility to assess whether the reasoning or methodology used by the proposed expert is scientifically valid and applies to the facts in dispute in the case. The Court should prevent the proposed expert from testifying if the proposed expert fails to meet any one of these four requirements.
In addition to that, the Court should prevent a person from testifying as an expert if the person’s testimony is speculative or unreliable. A good way for a proposed expert to avoid a claim that her testimony is speculative or unreliable is for the proposed expert to take measurements and samples, conduct tests, and subject her opinion to a peer review. Moreover, the Court should prevent a person from testifying as an expert if the person’s testimony is based only on her personal experience and training.
A litigant will be in a good position to help ensure her proposed expert gets to testify if that litigant understands the Court’s gatekeeping role and ensures her proposed expert satisfies all that is required. Similarly, a litigant may have the opportunity to convince the Court to prevent an opposing party’s proposed expert from testifying if it can be shown that that proposed expert does not satisfy the requirements listed above.