(a) Definition of unavailability. Unavailability as a witness includes situations in which the declarant:
(1) Is exempted by ruling of the judge on the ground of privilege from testifying concerning the subject matter of the declarant's statement; or
(2) Persists in refusing to testify concerning the subject matter of the declarant's statement despite an order of the judge to do so; or
(3) Testifies to a lack of memory of the subject matter of the declarant's statement; or
(4) Is unable to be present or to testify at the hearing because of death or then existing physical or mental illness or infirmity; or
(5) Is absent from the hearing and the proponent of a statement has been unable to procure the declarant's attendance (or in the case of a hearsay exception under paragraph (b) (2), (3), or (4) of this section, the declarant's attendance or testimony) by process or other reasonable means.
A declarant is not unavailable as a witness if exemption, refusal, claim of lack of memory, inability, or absence is due to the procurement or wrongdoing of the proponent of a statement for the purpose of preventing the witness from attending or testifying.
(b) Hearsay exceptions. The following are not excluded by the hearsay rule if the declarant is unavailable as a witness:
(1) Former testimony. Testimony given as a witness at another hearing of the same or a different proceeding, or in a deposition taken in compliance with law in the course of the same or another proceeding, if the party against whom the testimony is now offered, or a predecessor in interest, had an opportunity and similar motive to develop the testimony by direct, cross, or redirect examination.
(2) Statement under belief of impending death. A statement made by a declarant while believing that the declarant's death was imminent, concerning the cause or circumstances of what the declarant believed to be impending death.
(3) Statement against interest. A statement which was at the time of its making so far contrary to the declarant's pecuniary or proprietary interest, or so far tended to subject the declarant to civil or criminal liability, or to render invalid a claim by the declarant against another, that a reasonable person in the declarant's position would not have made the statement unless believing it to be true.
(4) Statement of personal or family history.
(i) A statement concerning the declarant's own birth, adoption, marriage, divorce, legitimacy, relationship by blood, adoption, or marriage, ancestry, or other similar fact of personal or family history, even though declarant had no means of acquiring personal knowledge of the matter stated; or
(ii) A statement concerning the foregoing matters, and death also, of another person, if the declarant was related to the other by blood, adoption, or marriage or was so intimately associated with the other's family as to be likely to have accurate information concerning the matter declared.
(5) Other exceptions. A statement not specifically covered by any of the foregoing exceptions but having equivalent circumstantial guarantees of trustworthiness to the aforementioned hearsay exceptions, if the judge determines that -
(i) The statement is offered as evidence of a material fact;
(ii) The statement is more probative on the point for which it is offered than any other evidence which the proponent can procure through reasonable efforts; and
(iii) The general purposes of these rules and the interests of justice will best be served by admission of the statement into evidence. However, a statement may not be admitted under this exception unless the proponent of it makes known to the adverse party sufficiently in advance of the hearing to provide the adverse party with a fair opportunity to prepare to meet it, the proponent's intention to offer the statement and the particulars of it, including the name and address of the declarant.