At the trial or upon

(d) USE OF DEPOSITIONS. the hearing of a motion or an interlocutory proceeding, any part or all of a deposition, so far as admissible under the rules of evidence, may be used against any party who was present or represented at the taking of the deposition or who had due notice thereof, in accordance with any one of the following provisions:

(1) Any deposition may be used by any party for the purpose of contradicting or impeaching the testimony of deponent as a witness.

(2) The deposition of a party or of any one who at the time of taking the deposition was an officer, director, or managing agent of a public or private corporation, partnership, or association which is a party may be used by an adverse party for any purpose.

(3) The deposition of a witness, whether or not a party, may be used by any party for any purpose if the court finds: 1, that the witness is dead; or 2, that the witness is at a greater distance than 100 miles from the place of trial or hearing, or is out of the United States, unless it appears that the absence of the witness was procured by the party offering the deposition; or 3, that the witness is unable to attend or testify because of age, sickness, infirmity, or imprisonment; or 4, that the party offering the deposition has been unable to procure the attendance of the witness by subpoena; or 5, upon application and notice, that such exceptional circumstances exist as to make it desirable, in the interest of justice and with due regard to the importance of presenting the testimony of witnesses orally in open court, to allow the deposition to he used.

(4) If only part of a deposition is offered in evidence by a party, an adverse party may require him to introduce all of it which is relevant to the part introduced, and any party may introduce any other parts.

Substitution of parties does not affect the right to use depositions previously taken; and, when an action in any court of the United States or of any state has been dismissed and another action involving the same subject matter is afterward brought between the same parties or their representatives or successors in interest, all depositions lawfully taken and duly filed in the former action may be used in the latter as if orginally taken therefor.

(e) OBJECTIONS TO ADMISSIBILITY. Subject to the provisions of Rule 32 (c), objection may be made at the trial or hearing to receiving in evidence any deposition or part thereof for any reason which would require the exclusion of the evidence if the witness were then present and testifying.

(f) EFFECT OF TAKING OR USING DEPOSITIONS. A party shall not be deemed to make a person his own witness for any purpose by taking his deposition. The introduction in evidence of the deposition or any part thereof for any purpose other than that of contradicting or impeaching the deponent makes the deponent the witness of the party introducing the deposition, but this shall not apply to the use by an adverse party of a deposition as described in paragraph (2) of subdivision (d) of this rule. At the trial or hearing any party may rebut any relevant evidence contained in a deposition whether introduced by him or by any other party.

Rule 27. Depositions Before Action or Pending Appeal.

(a) BEFORE ACTION.

(1) Petition. A person who desires to perpetuate his own testimony or that of another person regarding any matter that may be cognizable in any court of the United States may file a verified petition in the district court of the United States in the district of the residence of any expected adverse party. The petition shall be entitled in the name of the petitioner and shall show: 1, that the petitioner expects to be a party to an action cognizable in a court of the United States but is presently unable to bring it or cause it to be brought, 2, the subject matter of the expected action and his interest therein, 3, the facts which he desires to establish by the proposed testimony and his reasons for desiring to perpetuate it, 4, the names or a description of the persons he expects will be adverse parties and their addresses so far as known, and 5, the names and addresses of the persons to be examined and the substance of the testimony which he expects to elicit from each, and shall ask for an order authorizing the petitioner to take the depositions of the persons to be examined named in the petition, for the purpose of perpetuating their testimony.

(2) Notice and Service. The petitioner shall thereafter serve a notice upon each person named in the petition as an expected adverse party, together with a copy of the petition, stating that the petitioner will apply to the court, at a time and place named therein, for the order described in the petition. At least 20 days before the

date of hearing the notice shall be served either within or without the district or state in the manner provided in Rule 4 (d) for service of summons; but if such service cannot with due diligence be made upon any expected adverse party named in the petition, the court may make such order as is just for service by publication or otherwise, and shall appoint, for persons not served in the manner provided in Rule 4 (d), an attorney who shall represent them, and, in case they are not otherwise represented, shall cross-examine the deponent. If any expected adverse party is a minor or incompetent the provisions of Rule 17 (c) apply.

(3) Order and Examination. If the court is satisfied that the perpetuation of the testimony may prevent a failure or delay of justice, it shall make an order designating or describing the persons whose depositions may be taken and specifying the subject matter of the examination and whether the depositions shall be taken upon oral examination or written interrogatories. The depositions may then be taken in accordance with these rules. For the purpose of applying these rules to depositions for perpetuating testimony, each reference therein to the court in which the action is pending shall be deemed to refer to the court in which the petition for such deposition was filed.

(4) Use of Deposition. If a deposition to perpetuate testimony is taken under these rules or if, although not so taken, it would be admissible in evidence in the courts of the state in which it is taken, it may be used in any action involving the same subject matter subsequently

brought in a district court of the United States, in accordance with the provisions of Rule 26 (d). (b) PENDING APPEAL. If an appeal has been taken from a judgment of a district court or before the taking of an appeal if the time therefor has not expired, the district court in which the judgment was rendered may allow the taking of the depositions of witnesses to perpetuate their testimony for use in the event of further proceedings in the district court. In such case the party who desires to perpetuate the testimony may make a motion in the district court for leave to take the depositions, upon the same notice and service thereof as if the action was pending in the district court. The motion shall show (1) the names and addresses of the persons to be examined and the substance of the testimony which he expects to elicit from each; (2) the reasons for perpetuating their testimony. If the court finds that the perpetuation of the testimony is proper to avoid a failure or delay of justice, it may make an order allowing the depositions to be taken, and thereupon the depositions may be taken and used in the same manner and under the same conditions as are prescribed in these rules for depositions taken in actions pending in the district court.

(c) PERPETUATION BY ACTION. This rule does not limit the power of a court to entertain an action to perpetuate testimony.

Rule 28. Persons Before Whom Depositions May Be Taken.

(a) WITHIN THE UNITED STATES. Within the United States or within a territory or insular possession subject to the dominion of the United States, depositions shall be taken before an officer authorized to administer oaths by the laws of the United States or of the place where the examination is held