Rule 705 – Disclosing the Facts or Data Underlying an Expert’s Opinion

Unless the court orders otherwise, an expert may state an opinion — and give the reasons for it — without first testifying to the underlying facts or data. But the expert may be required to disclose those facts or data on cross-examination.

(Pub.L. 93-595, § 1, Jan. 2, 1975, 88 Stat. 1938; Mar. 2, 1987, eff. Oct. 1, 1987; Apr. 22, 1993, eff. Dec. 1, 1993; Apr. 26, 2011, eff. Dec. 1, 2011.)