
394 Mass. 531 (1985)
476 N.E.2d 593
COMMONWEALTH
vs.
JAMES M. KATER.
Supreme Judicial Court of Massachusetts, Bristol.
February 6, 1985.
April 11, 1985.
Present: HENNESSEY, C.J., WILKINS, LYNCH, & O'CONNOR, JJ.
Jonathan Shapiro (Patricia Garin with him) for the defendant.
Phillip L. Weiner, Assistant District Attorney, for the Commonwealth.
O'CONNOR, J.
Over two years ago, we reversed James M. Kater's convictions for murder in the first degree and kidnapping because the introduction at his trial of hypnotically aided testimony  testimony first available from a witness after hypnosis  created a substantial risk that a miscarriage of justice had occurred. Commonwealth v. Kater, 388 Mass. 519, 521, 534 (1983) (Kater I). We did not order the indictments dismissed. Instead, because we concluded that during the trial the Commonwealth had introduced sufficient evidence, other *532 than the hypnotically aided testimony, to warrant guilty verdicts, we ordered a new trial. Id. at 521. We announced that the hypnotized witnesses may testify at a retrial only as to their memory of events known to them prior to hypnosis. Id. at 534. Furthermore, we authorized the defendant to present evidence "bearing on the effect of hypnosis on a particular witness and on witnesses in general" and evidence "tending to show that each hypnotic session, and any attempted hypnotic session, was conducted in a manner likely to affect both a witness's present memory of events and a witness's degree of confidence in his or her memory," and we authorized the Commonwealth to present evidence to the contrary. Id. at 535. Although we recognized that that solution was not entirely satisfactory because "[i]t will not be easy for lay witnesses to limit themselves to their prehypnotic memory," we declined to adopt a solution that would have barred the formerly hypnotized witness from testifying at the retrial or one that would have allowed those witnesses to give hypnotically aided testimony. Id.
In November, 1983, in anticipation of retrial, Kater filed in the Superior Court a motion to suppress the testimony of all formerly hypnotized witnesses, and, in February, 1984, a judge commenced a hearing to determine what part, if any, of those witnesses' testimony he would allow at the retrial. Helena McCoy, who was one of the hypnotized witnesses, testified at that hearing, as did a police officer and two hypnosis experts.
After having participated in the hearing to that point, the Commonwealth, describing the hearing as "an unnecessary step," filed a motion to terminate it. The judge agreed, allowed the Commonwealth's motion to terminate the hearing, and denied Kater's motion to suppress. The judge concluded that it was not his function "to determine what is, and is not, a witness's present memory of events known prior to hypnosis." Instead, the judge declared that he would instruct the hypnotized witnesses to limit their testimony to prehypnotic memory to the best of their ability. Pursuant to Mass. R. Crim. P. 34, 378 Mass. 905 (1979),[1] the judge reported the case to the *533 Appeals Court. We granted Kater's application for direct appellate review.
We hold that the judge should not have terminated the hearing. Kater I holds that hypnotically aided testimony is inadmissible in criminal trials in this Commonwealth, including Kater's trial. Because the hypnotic sessions involved in this case occurred before the date of our opinion in Kater I, the Commonwealth's failure to conduct the sessions in accordance with the procedural safeguards enumerated in Commonwealth v. A Juvenile, 381 Mass. 727, 732 n. 8 (1980), does not make inadmissible testimony based on a witness's prehypnotic memory. Kater I, supra at 521, 530. Nevertheless, that testimony must be separated from hypnotically aided testimony, which is inadmissible. Since the question of admissibility is for the judge, Kater I, supra at 531, before admitting proffered testimony, the judge must be satisfied by a preponderance of the evidence presented at a hearing that the testimony is based on prehypnotic memory.
We remand this case to the Superior Court for further proceedings consistent with this opinion.
So ordered.
NOTES
[1]  Rule 34 provides: "If, prior to trial, or, with the consent of the defendant, after conviction of the defendant, a question of law arises which the trial judge determines is so important or doubtful as to require the decision of the Appeals Court, the judge may report the case so far as necessary to present the question of law arising therein. If the case is reported prior to trial, the case shall be continued for trial to await the decision of the Appeals Court."
