Basis of Opinion Testimony by Experts — Rule 703

• Jurisdiction: Colorado

Basis of Opinion Testimony by Experts — Rule 703

SUMMARY OF RULE 703

• Facts or data used by an expert may be those perceived or made known at or before a hearing.
• If the information is the type reasonably relied on by experts in a particular field, facts or data need not be admissible in evidence.
• An expert may testify to opinion without first testifying to the underlying facts or data (unless the court requests otherwise). The expert may be required to disclose underlying facts or data on cross-examination (CRE 705).

LEGAL AUTHORITIES

• A police officer may offer lay opinion testimony based on perceptions and experience. If the opinion involves expertise in determining a certain fact, the officer must be qualified as an expert. People v. Stewart, 55 P.3d 107 (Colo. 2002).

• An expert may base an opinion on a hypothetical question. Gold Rush Investments, Inc. v. G.E. Johnson Constr. Co., Inc., 807 P.2d 1169 (Colo. App. 1990).

• An expert may be asked hypothetical questions based on assumptions when the assumptions have a reasonable basis in the evidence. Roberts v. C & M Ready Mix Concrete Co., 767 P.2d 769 (Colo. App. 1988).

• Hypothetical facts or assumptions should be supported by the evidence. Form and admissibility is left to the trial court's discretion. People v. Nhan Dao Van, 681 P.2d 932 (Colo. 1984).

• An expert may base his or her opinion on opinions of other experts if the other opinions are outside the expert's area of expertise, the other experts were subject to cross-examination, and the opinions were of the type reasonably relied on by experts in the field. Gold Rush Investments, Inc. v. G.E. Johnson Constr. Co., Inc., 807 P.2d 1169 (Colo. App. 1990).

• An expert may not base his or her opinion or conclusion solely on the opinions of outside experts. People v. Beasley, 608 P.2d 835 (Colo. App. 1979).

• An expert may be cross-examined on learned treatises even if the expert did not rely on a treatise. People v. Beasley, 608 P.2d 835 (Colo. App. 1979).

• Failure to offer the witness as an expert may preclude the ability to ask expert opinions from the witness. People v. Stewart, 55 P.3d 107 (Colo. 2002).

• An expert may not be allowed to interview a child if the interview would be too traumatic, and prior interviews by other experts were videotaped, audiotaped, or transcribed. People ex rel. E.S., 49 P.3d 1221 (Colo. App. 2002).

• An expert may describe statements or reports relied on, but CRE 703 does not permit otherwise inadmissible...