Current through Register Vol. 54, No. 38, September 21, 2024
(a) Discovery of facts known and opinions
held by an expert, otherwise discoverable under the provisions of Rule
4003.1 and acquired or developed
in anticipation of litigation or for trial, may be obtained as follows:
(1) A party may through interrogatories
require
(A) any other party to identify each
person whom the other party expects to call as an expert witness at trial and
to state the subject matter on which the expert is expected to testify
and
(B) subject to the provisions
of subdivision (a)(4), the other party to have each expert so identified state
the substance of the facts and opinions to which the expert is expected to
testify and a summary of the grounds for each opinion. The party answering the
interrogatories may file as his or her answer a report of the expert or have
the interrogatories answered by the expert. The answer or separate report shall
be signed by the expert.
(2) Upon cause shown, the court may order
further discovery by other means, subject to
(A) such restrictions as to scope and such
provisions concerning fees and expenses as the court may deem appropriate,
and
(B) The provisions of
subdivision (a)(4) of this rule.
(3) A party may not discover facts known or
opinions held by an expert who has been retained or specially employed by
another party in anticipation of litigation or preparation for trial and who is
not expected to be called as a witness at trial, except a medical expert as
provided in Rule 4010(b) or except on order of court as to any other expert
upon a showing of exceptional circumstances under which it is impracticable for
the party seeking discovery to obtain facts or opinions on the same subject by
other means, subject to such restrictions as to scope and such provisions
concerning fees and expenses as the court may deem appropriate.
(4) A party may not discover the
communications between another party's attorney and any expert who is to be
identified pursuant to subdivision (a)(1)(A) or from whom discovery is
permitted under subdivision (a)(3) regardless of the form of the
communications, except in circumstances that would warrant the disclosure of
privileged communications under Pennsylvania law. This provision protects from
discovery draft expert reports and any communications between another party's
attorney and experts relating to such drafts.
(b) An expert witness whose identity is not
disclosed in compliance with subdivision (a)(1) of this rule shall not be
permitted to testify on behalf of the defaulting party at the trial of the
action. However, if the failure to disclose the identity of the witness is the
result of extenuating circumstances beyond the control of the defaulting party,
the court may grant a continuance or other appropriate relief.
(c) To the extent that the facts known or
opinions held by an expert have been developed in discovery proceedings under
subdivision (a)(1) or (2) of this rule, the direct testimony of the expert at
the trial may not be inconsistent with or go beyond the fair scope of his or
her testimony in the discovery proceedings as set forth in the deposition,
answer to an interrogatory, separate report or supplement thereto. However, the
expert shall not be prevented from testifying as to facts or opinions on
matters on which the expert has not been interrogated in the discovery
proceedings.
