Section 18.51 - Discovery scope and limits(a)Scope in general. Unless otherwise limited by a judge's order, the scope of discovery is as follows: Parties may obtain discovery regarding any nonprivileged matter that is relevant to any party's claim or defense-including the existence, description, nature, custody, condition, and location of any documents or other tangible things and the identity and location of persons who know of any discoverable matter. For good cause, the judge may order discovery of any matter relevant to the subject matter involved in the proceeding. Relevant information need not be admissible at the hearing if the discovery appears reasonably calculated to lead to the discovery of admissible evidence. All discovery is subject to the limitations imposed by paragraph (b)(4) of this section.(b)Limitations on frequency and extent -(1)When permitted. By order, the judge may alter the limits in these rules on the number of depositions and interrogatories or on the length of depositions under § 18.64 . The judge's order may also limit the number of requests under § 18.63 .(2)Specific limitations on electronically stored information. A party need not provide discovery of electronically stored information from sources that the party identifies as not reasonably accessible because of undue burden or cost. On motion to compel discovery or for a protective order, the party from whom discovery is sought must show that the information is not reasonably accessible because of undue burden or cost. If that showing is made, the judge may nonetheless order discovery from such sources if the requesting party shows good cause, considering the limitations of paragraph (b)(4) of this section. The judge may specify conditions for the discovery.(3)Inadvertently disclosed privileged or protected information. By requesting electronically stored information, a party consents to the application of Federal Rule of Evidence 502 with regard to inadvertently disclosed privileged or protected information.(4)When required. On motion or on his or her own, the judge must limit the frequency or extent of discovery otherwise allowed by these rules when: (i) The discovery sought is unreasonably cumulative or duplicative, or can be obtained from some other source that is more convenient, less burdensome, or less expensive;(ii) The party seeking discovery has had ample opportunity to obtain the information by discovery in the action; or(iii) The burden or expense of the proposed discovery outweighs its likely benefit, considering the needs of the case, the amount in controversy, the parties' resources, the importance of the issues at stake in the action, and the importance of the discovery in resolving the issues.(c)Hearing preparation: Materials -(1)Documents and tangible things. Ordinarily, a party may not discover documents and tangible things that are prepared in anticipation of litigation or for hearing by or for another party or its representative (including the other party's attorney, consultant, surety, indemnitor, insurer, or agent). But, subject to paragraph (d) of this section, those materials may be discovered if: (i) They are otherwise discoverable under paragraph (a) of this section; and(ii) The party shows that it has substantial need for the materials to prepare its case and cannot, without undue hardship, obtain their substantial equivalent by other means.(2)Protection against disclosure. A judge who orders discovery of those materials must protect against disclosure of the mental impressions, conclusions, opinions, or legal theories of a party's representative concerning the litigation.(3)Previous statement. Any party or other person may, on request and without the required showing, obtain the person's own previous statement about the action or its subject matter. If the request is refused, the person may move for a judge's order. A previous statement is either:(i) A written statement that the person has signed or otherwise adopted or approved; or(ii) A contemporaneous stenographic, mechanical, electrical, or other recording-or a transcription of it-that recites substantially verbatim the person's oral statement.(d)Hearing preparation: Experts - (1)Deposition of an expert who may testify. A party may depose any person who has been identified as an expert whose opinions may be presented at trial. If § 18.50(c)(2)(ii) requires a report from the expert the deposition may be conducted only after the report is provided, unless the parties stipulate otherwise.(2)Hearing-preparation protection for draft reports or disclosures. Paragraphs (c)(1) and (2) of this section protect drafts of any report or disclosure required under § 18.50(c)(2) , regardless of the form in which the draft is recorded.(3)Hearing-preparation protection for communications between a party's representative and expert witnesses. Paragraphs (c)(1) and (2) under this section protect communications between the party's representative and any witness required to provide a report under § 18.50(c)(2)(ii) , regardless of the form of the communications, except to the extent that the communications:(i) Relate to compensation for the expert's study or testimony;(ii) Identify facts or data that the party's representative provided and that the expert considered in forming the opinions to be expressed; or(iii) Identify assumptions that the party's representative provided and that the expert relied on in forming the opinions to be expressed.(4)Expert employed only for hearing preparation. Ordinarily, a party may not, by interrogatories or deposition, discover facts known or opinions held by an expert who has been retained or specially employed by another party in anticipation of litigation or to prepare for hearing and whose testimony is not anticipated to be used at the hearing. But a party may do so only:(i) As provided in § 18.62(c) ; or(ii) On showing exceptional circumstances under which it is impracticable for the party to obtain facts or opinions on the same subject by other means.(e)Claiming privilege or protecting hearing-preparation materials -(1)Information withheld. When a party withholds information otherwise discoverable by claiming that the information is privileged or subject to protection as hearing-preparation material, the party must: (i) Expressly make the claim; and(ii) Describe the nature of the documents, communications, or tangible things not produced or disclosed-and do so in a manner that, without revealing information itself privileged or protected, will enable other parties to assess the claim.(2)Information produced. If information produced in discovery is subject to a claim of privilege or of protection as hearing-preparation material, the party making the claim must notify any party that received the information of the claim and the basis for it. After being notified, a party must promptly return, sequester, or destroy the specified information and any copies it has; must not use or disclose the information until the claim is resolved; must take reasonable steps to retrieve the information if the party disclosed it before being notified; and may promptly present the information to the judge for an in camera determination of the claim. The producing party must preserve the information until the claim is resolved.80 FR 28785, May 19, 2015, as amended at 80 FR 37539, July 1, 2015