Federal evidence rules 702-703 govern admissibility of expert testimony. There are 3 questions to ask: 

  • Is the opinion rational? Testimony must be confined to: a) expert’s area of expertise b) be rationally related to data c) not contradict basic scientific principles d) be derived by following accepted procedures, practices e) be scientifically reliable per the Daubert test.
  • The Supreme Court Daubert case also mentioned the following: a) subject to peer review b) have small error rate c) have achieved widespread acceptance. Qualifications-In addition to the above, the expert must be familiar with the case.
  • The opinion can even be based on inadmissible evidence, or be adopted from other experts. Opinions on Ultimate issues vs Legal conclusions: An expert opinion is admissible even though it embraces an ultimate fact in issue or invades the province of the jury, as long as it embraces an area in the expert’s field of specialty.
  1. Is there an appropriate issue for expert testimony? Experts may testify whenever their specialized knowledge will assist the jury, which is very often.
  2. Does the witness have the qualifications to be an expert? The skill, experience, training/education will also be looked at.
  3. Is the expert basing opinions on sufficient information? There must be enough information to be reliable.