No later than ten days prior to trial or at such time as the court permits, or at the time of any post-indictment pretrial evidentiary hearing other than a bond hearing, the prosecution or the defendant shall produce for the opposing party any statement of any witness that is in the possession, custody, or control of the state or prosecution or in the possession, custody, or control of the defendant or the defendant's counsel that relates to the subject matter concerning the testimony of the witness that the party in possession, custody, or control of the statement intends to call as a witness at trial or at such post-indictment pretrial evidentiary hearing.
Georgia Legal Code