In which scenario would an expert's opinion be inadmissible under Rule 702?

An expert's opinion would be deemed inadmissible under Rule 702 if it is based solely on hearsay. Rule 702 of the Federal Rules of Evidence outlines the criteria under which expert testimony may be admissible, requiring that the expert's opinion be based on sufficient facts or data, be the product of reliable principles and methods, and that the expert has reliably applied those principles and methods to the facts of the case.

When an expert's opinion is based solely on hearsay, it does not meet the necessary standard of reliability and credibility required by Rule 702. Hearsay refers to statements made outside of court that are offered in court for the truth of the matter asserted, which undermines the foundational reliability of the expert's conclusions. Such an opinion lacks the necessary evidential support of firsthand knowledge or verifiable factual basis that would otherwise qualify it for admissibility. Hence, relying solely on hearsay not only compromises the integrity of the expert's testimony but also fails to fulfill the evidentiary standards necessary for the court's consideration.