Courts are wary about permitting witnesses to testify about events after they have been subjected to hypnosis to confirm or improve upon the witness’s memory. A major difficulty with post-hypnotic testimony is the danger that hypnosis may artificially enhance a witness’s confidence in the prior recollection, and this in turn could inhibit meaningful cross-examination.36 The pre-trial use of hypnosis does not necessarily render the witness incompetent to testify to events recalled prior to being hypnotized. If a witness has been hypnotized, however, the court must conduct a hearing to determine whether hypnosis has substantially impaired the ability to cross-examine the witness or was otherwise improper. The court must first decide whether the scope of the witness’s pre-hypnotic recollection can be reliably determined by evidence. The court must next determine whether the party seeking to introduce the testimony has shown by clear and convincing evidence that hypnosis did not so enhance the witness’s confidence in the earlier recollection that the opposing party’s right to cross-examine has been substantially impaired. In making such a determination, the court must consider (1) the amount of confidence the witness had in the initial recollection prior to being hypnotized; (2) the extent of the witness’s belief in the ability of hypnosis to yield the truth; (3) the degree to which the witness was hypnotized; (4) the length of the hypnotic session; (5) the type and nature of questioning employed during the hypnotic session; and (6) any other factors which the court may deem important based upon the specific facts and circumstances of the case.37
If the witness had no recollection of events prior to hypnosis, a witness may not testify as to events recalled as a result of the hypnosis, as the scientific reliability of such a method of recollection has not yet been proven.38
36. Elliotte v. State, 515 A.2d 677, 679 (Del. 1986).
37. Elliotte v. State, 515 A.2d 677, 681-82 (Del. 1986). Judge Trucking Co., Inc. v. Estate of Cooper, Cons. C.A. No. 92C-04-023, 93C-04-023 & 93C-07-025, slip op. at 6-7, Graves, J. (Del. Super. Dec. 6, 1994).
38. State v. Davis, 490 A.2d 601, 604 (Del. Super. 1985).
© 2010 David L. Finger