Expert Witnesses in Indiana
In Indiana, an expert witness is a qualified specialist whose knowledge, skill, experience, training, or education helps the trier of fact understand evidence or resolve a disputed issue.
Rules Governing Disclosure
A party may discover facts known and opinions held by experts through interrogatories. Indiana Trial Rule 26(B)(4)(a)(i) allows a party, by interrogatory, to require another party to identify each expert expected to testify at trial and to state:
the subject matter on which the expert is expected to testify;
the substance of the facts and opinions to which the expert is expected to testify; and
a summary of the grounds for each opinion.
Admissibility Standards
In Indiana, the admissibility of expert testimony is governed mainly by Indiana Rule of Evidence 702. An expert may testify if the witness is qualified by knowledge, skill, experience, training, or education, and the expert’s scientific, technical, or other specialized knowledge will help the trier of fact understand the evidence or determine a fact in issue.
For scientific expert testimony, Indiana has an additional reliability requirement. Rule 702(b) provides that scientific expert testimony is admissible only if the court is satisfied that the testimony rests on reliable scientific principles.
To put it simply, Indiana follows a Rule 702 reliability framework that is influenced by Daubert, while rejecting Frye’s strict general-acceptance test as the controlling standard.
Attorney–Expert Communication Protection
Indiana does not categorically shield attorney–expert communications; instead, it protects the mental impressions, conclusions, opinions, or legal theories of an attorney through work-product doctrine while allowing discovery of testifying experts’ opinions, factual bases, and grounds.
Compensation
Indiana Trial Rule 26(B)(4)(c) requires the party seeking expert discovery to pay the expert a reasonable fee for time spent responding to discovery, unless manifest injustice would result, and may also require payment of a fair portion of the opposing party’s expert-related fees and expenses in certain circumstances.
Limits on Number of Expert Witnesses
However, Indiana courts can limit the number of expert witnesses through case-management or pretrial orders. Indiana Trial Rule 16 allows the court at a pretrial conference to consider “a limitation of the number of expert witnesses.”
Out-of-State Expert Qualification
Indiana does not appear to impose a special in-state residency requirement for expert witnesses. An out-of-state expert can qualify if they satisfy the ordinary Indiana expert-testimony standard under Indiana Rule of Evidence 702.
In medical-malpractice or professional-standard cases, the out-of-state issue may matter more practically. The expert may need to show familiarity with the applicable standard of care and the professional context relevant to the defendant’s conduct. But Indiana’s general evidentiary rule still looks to qualifications, reliability, and helpfulness rather than imposing a blanket Indiana-only requirement.
