Use of Deposition

At the trial or upon any hearing, a part or all of a deposition, so far as otherwise admissible under the rules of evidence, may be used a substantive evidence if the witness is unavailable, as defined in § 70.75, or the witness gives testimony at the trial or hearing inconsistent with his deposition. Any deposition may also be used by any party for the purpose of contradicting or impeaching the testimony of the deponent as a witness. If only a part of a deposition is offered in evidence by a party, an adverse party may require him to offer all of it which is relevant to the part offered and any party may offer other parts.