Rule 705.?Disclosingthe Facts or Data Underlying an Expert?s Opinion.
Unlessthe court orders otherwise, an expert may state an opinion ? and give thereasons for it ? without first testifying to the underlying facts or data. Butthe expert may be required to disclose those facts or data oncross-examination.
2011 Advisory Committee Note.?The language of this rule has been amended as part of therestyling of the Evidence Rules to make them more easily understood and to makestyle and terminology consistent throughout the rules. These changes areintended to be stylistic only. There is no intent to change any result in anyruling on evidence admissibility. This rule is the federal rule, verbatim.
Original Advisory Committee Note.?This rule is the federal rule, verbatim. The substance of thisrule was formerly found in Rules 57 and 58, Utah Rules of Evidence (1971). Therequirement that an expert disclose the underlying facts or data for hisopinion when cross-examined was formerly found in Rule 58, Utah Rules ofEvidence (1971). The discretion vested in the trial judge to require priordisclosure of underlying facts or data should be liberally exercised insituations where there has not been adequate discovery in civil cases ordisclosure in criminal cases.