What does Ohio require an expert to disclose before testifying?

In Ohio, the requirement for an expert to disclose the basis of their opinion before testifying is crucial for establishing the credibility and relevance of their testimony. This ensures that the opinion provided is grounded in reliable principles and methodologies, which can be scrutinized for validity. By requiring the expert to disclose the basis of their opinion, it allows the court and jury to understand how the expert arrived at their conclusions and whether those conclusions are scientifically or professionally sound.

This requirement also supports the fairness of the trial process by enabling opposing parties to examine the foundation of the expert's opinions, fostering a more informed evaluation of the evidence presented. While qualifications, final conclusions, and specific methodologies are important components in assessing an expert's testimony, the emphasis in Ohio law on the basis of the expert's opinion specifically highlights its role in ensuring that the opinion is not merely subjective but instead rooted in demonstrable evidence and relevant standards.