§ RULE 5-703 BASES OF OPINION TESTIMONY BY EXPERTS

RULE 5-703. BASES OF OPINION TESTIMONY BY EXPERTS

    (a) In General. The facts or data in the particular case upon which an expert bases an opinion or inference may be those perceived by or made known to the expert at or before the hearing. If of a type reasonably relied upon by experts in the particular field in forming opinions or inferences upon the subject, the facts or data need not be admissible in evidence.

    (b) Disclosure to Jury. If determined to be trustworthy, necessary to illuminate testimony, and unprivileged, facts or data reasonably relied upon by an expert pursuant to section (a) may, in the discretion of the court, be disclosed to the jury even if those facts and data are not admissible in evidence. Upon request, the court shall instruct the jury to use those facts and data only for the purpose of evaluating the validity and probative value of the expert's opinion or inference.

    (c) Right to Challenge Expert. This Rule does not limit the right of an opposing party to cross-examine an expert witness or to test the basis of the expert's opinion or inference.

    Committee note: Subject to Rule 5-403, and in criminal cases the confrontation clause, experts who rely on information from others may relate that information in their testimony if it is of a type reasonably relied upon by experts in the field. If it is inadmissible as substantive proof, it comes in merely to explain the factual basis for the expert opinion. The opposing party then is entitled to an instruction to the jury that it may consider the evidence only for that limited purpose. See, e.g., Maryland Dept. of Human Resources v. Bo Peep Day Nursery, 317 Md. 573 (1989); Attorney Grievance Commission v. Nothstein, 300 Md. 667 (1984); Beahm v. Shortall, 279 Md. 321 (1977); Hartless v. State, 327 Md. 558 (1992).

    Source: Section (a) of this Rule is derived from F.R.Ev. 703. Sections (b) and (c) are derived from Ky.R.Ev. 703(b) and (c).