Under Rule 703, may an expert base an opinion on facts or data that are not admissible themselves?

• A. An expert may base an opinion only on admissible facts or data.
• B. An expert may base an opinion on facts or data, even if inadmissible, if reasonably relied upon by experts in the field; and those inadmissible facts may be disclosed to help the jury if probative value outweighs prejudicial effect.
• C. An expert may not disclose inadmissible data under any circumstances.
• D. An expert may rely on inadmissible facts only if the court orders such disclosure.

Answer: (B)

Under Rule 703, an expert may base an opinion on facts or data that are not admissible themselves, as long as those facts or data are of a type reasonably relied upon by experts in the field. The rule recognizes that specialists often rely on sources or data that aren’t admitted as evidence, but which are essential to forming a reasoned opinion. Importantly, the inadmissible data may be disclosed to the jury to aid understanding if the value of that information in proving the opinion outweighs any prejudicial effect. This balances the need for expert reasoning with the trial’s evidentiary safeguards.

So the best choice reflects that admissible reliance is not required, but the data must be the kind experts reasonably rely on, and disclosure to the jury is allowed only if its probative value outweighs potential prejudice. The alternatives either overstate the restriction, prohibit disclosure, or make disclosure depend solely on a court order, which isn’t how Rule 703 operates.