You have a right to obtain copies of both, the transcription and the tape, during discovery and otherwise in the lawsuit. Have your attorney obtain both.
Transcripts are only done for convenience and they are sometimes good and sometimes not so good.
This answer is provided for informational purposes only. Actual legal advice can only be provided in an office consultation by an attorney licensed in your jurisdiction, with experience in the area of law in which your concern lies.
If this is a personal injury case, you should avail yourself of Mass. Gen. Laws c. 233, sec. 23A:
Chapter 233: Section 23A. Admissibility of written or recorded statements of party to personal injury action
Section 23A. In any action to recover damages for personal injuries or consequential damages, so called, resulting therefrom, no statement in writing signed by any party to the action or statement taken on a recording instrument, concerning the facts out of which the cause of action arose, given by such party, or a person in his behalf, to any other party to the action, or to his agent or attorney, or to the insurer of such other party, or to the agent or attorney of such insurer, shall be admissible in evidence in, or referred to at, the trial of such action or in any proceeding connected therewith unless a copy of such statement or verbatim written transcription of such recorded statement is furnished to the party making the same or to his attorney within ten days after written request therefor made by such party or attorney to the adverse party or his attorney, or within such further time as the court may allow on motion and notice.
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