Pennsylvania Expert Witness Report Rules

Are Expert Witness Reports Required in Pennsylvania?

In Pennsylvania, the requirement for expert witness reports differs from many jurisdictions. Under Pennsylvania Rule of Civil Procedure 4003.5(a)(1), parties are not mandated to exchange formal expert reports in every case. Instead, the rule requires parties to respond to expert interrogatories. This means that a party can request, via interrogatories, that the opposing party identifies each expert expected to testify and discloses "the substance of the facts and opinions" to which the expert is expected to testify, along with a summary of the grounds for each opinion (Pa. R.C.P. 4003.5(a)(1)). Reports, if used, must be disclosed in accordance with the timeline set by the court, often as directed by a case management order.

What is Required in a Pennsylvania Expert Witness Report?

When a party elects to attach an expert's report as an answer to interrogatories, the expert witness report must be signed by the expert (Pa. R.C.P. 4003.5(a)(1)). While Pennsylvania does not require a formal report for every case, when used, the report should include:

• The substance of the expert's opinions
• The factual basis for each opinion
• Any data considered by the expert
• Exhibits to be used
• The expert’s qualifications
• Details on the expert's compensation

Unlike the federal standard, Pennsylvania allows the responding party to provide a detailed summary instead of a formal report, unless the court orders otherwise.

Scope and Authorship of the Report

In Pennsylvania, expert reports may be drafted with the involvement of counsel, but the expert must sign the report if it is attached to the interrogatory responses (Pa. R.C.P. 4003.5(a)(1)). Attorney involvement is permissible to ensure the report covers necessary legal elements, but the report must reflect the expert's own opinions and bases. The scope of the report can vary depending on the case type and complexity, as well as specific court orders.

Missing, Deficient, and Untimely Reports

Failure to provide an expert report or summary, or providing one that is deficient or late, can lead to significant consequences. Under Pa. R.C.P. 4003.5(b), an expert not disclosed in compliance with these rules shall be barred from testifying for the defaulting party at trial. Courts may exclude testimony, impose sanctions, or grant continuances in response to failures in meeting disclosure requirements. The enforcement of these rules ensures adherence to procedural fairness and trial readiness.

Original, Supplemental, and Rebuttal Reports

Pennsylvania rules do not explicitly distinguish between original, supplemental, and rebuttal reports as in the federal system. However, the timing and necessity of supplemental disclosures are typically governed by case management orders, and the content must remain within the fair scope of initial disclosures (Pa. R.C.P. 4003.5(b)). Disputes over supplemental or rebuttal reports are handled based on the specifics of case law and judicial discretion.

Relevant State Rules and Legal Requirements

The governing rule for expert disclosures in Pennsylvania is primarily found in Pa. R.C.P. 4003.5(a)-(c). Key appellate interpretations of this rule emphasize the necessity of providing complete and timely expert disclosures within the framework of the discovery process. Notably, Pennsylvania's approach diverges from federal practice by not routinely requiring depositions of experts unless ordered by the court (Pa. R.C.P. 4003.5(a)(2)). This reflects a distinctive procedural posture that balances the need for expert testimony with protections against undue burdens.