Cultic Studies Journal, Vol. 15, No. 1, 1998, page 52
In Favor of a Per Se Exclusion of Hypnotically Influenced Testimony:
a reply to Hoover
Robert A. Karlin, Ph.D.
Rutgers University
Martin T. Orne, M.D., Ph.D.
University of Pennsylvania
Hoover (1998) begins his comments by saying, “Karlin and Orne‟s position supporting the
per se exclusion of hypnotically refreshed testimony is plainly shaped by their experience of
the use of hypnosis in therapeutic settings.” In this, he is simply incorrect. Our opposition to
admitting the testimony of a previously hypnotized witness was shaped by the results of
scientific studies and by our experience with hypnosis in forensic settings (not in therapeutic
ones). This evolution can be seen in a change of positions from Orne (1979), which
suggested safeguards for forensic hypnosis to Orne, Soskis, Dinges, &Carota-Orne (1984),
which advocated a per se exclusion.
Although it was obvious early on that there were problems with the use of hypnosis with
witnesses who might testify, Orne had wanted to develop safeguards in order to preserve
the use of hypnosis, especially in the context of law enforcement, for the rare case in which
hypnosis might have more probative than prejudicial effect. But by 1982, it had become
apparent to Orne, Diamond, Levitt, Karlin and a variety of others, that they were seeing no
cases in which hypnosis had served the cause of justice, and any number in which hypnosis
either produced, or could well have produced, a serious miscarriage of justice (cf. Karlin,
1983).
There were and are reasons for this. The person who agrees to be hypnotized and
undergoes a formal induction must, to fulfill his role, alter his expectancies, behavior, and
view of the world. Inherent in this altered role is a decrease in critical judgment. One cannot
participate in even the simplest hypnotic suggestion (e.g., as you begin to feel a force
pulling your hands together, they will move together by themselves) without such a
decrease. Otherwise one would simply respond to such suggestions by saying “that is
absurd.” Taken together, the demands of a hypnotic role and the inherent decreased critical
judgment allow a blurring of the boundary between fantasy and memory, an increase in
certainty unrelated to accuracy, a tendency to misattribute whether information was learned
during hypnosis or before it, and a willingness to accept even a major change in memory as
credible.
Further, if a subject is relatively highly hypnotizable, the suggestions to relive events that
routinely follow hypnotic induction in the forensic context may have additional effects. First,
the frequent inclusion of confabulated, vivid detail in the new material makes hypnotically
influenced memories more credible (Dywan, 1995). Also, fantasies entirely unrelated to
what actually occurred may also be suggested during hypnosis and remembered as veridical
(Laurence, Nadon, Nogrady, &Perry, 1986). This is especially the case when there are no
clear original memories to overlay (cf. Orne, 1979 see also Karlin, 1983) or when, as in
civil cases, the hypnotized party has a strong interest in “remembering” one version of
events (cf. Karlin, 1997 Sprynczynatyk v. General Motors, 1985). Finally, more highly
hypnotizable subjects may subjectively relive events and vividly experience a version of the
past. Unfortunately, vividness has no relation to historical accuracy, but again increases
confidence inappropriately (cf. Frankel, 1994). In summary, we find a formidable basis for
automatically keeping hypnotically influenced testimony out of court.
As Mr. Hoover says, the problem in presenting this point of view at this time is both that it
1) seems rigid and 2) stands against the legal tide represented by the changes in the
In Favor of a Per Se Exclusion of Hypnotically Influenced Testimony:
a reply to Hoover
Robert A. Karlin, Ph.D.
Rutgers University
Martin T. Orne, M.D., Ph.D.
University of Pennsylvania
Hoover (1998) begins his comments by saying, “Karlin and Orne‟s position supporting the
per se exclusion of hypnotically refreshed testimony is plainly shaped by their experience of
the use of hypnosis in therapeutic settings.” In this, he is simply incorrect. Our opposition to
admitting the testimony of a previously hypnotized witness was shaped by the results of
scientific studies and by our experience with hypnosis in forensic settings (not in therapeutic
ones). This evolution can be seen in a change of positions from Orne (1979), which
suggested safeguards for forensic hypnosis to Orne, Soskis, Dinges, &Carota-Orne (1984),
which advocated a per se exclusion.
Although it was obvious early on that there were problems with the use of hypnosis with
witnesses who might testify, Orne had wanted to develop safeguards in order to preserve
the use of hypnosis, especially in the context of law enforcement, for the rare case in which
hypnosis might have more probative than prejudicial effect. But by 1982, it had become
apparent to Orne, Diamond, Levitt, Karlin and a variety of others, that they were seeing no
cases in which hypnosis had served the cause of justice, and any number in which hypnosis
either produced, or could well have produced, a serious miscarriage of justice (cf. Karlin,
1983).
There were and are reasons for this. The person who agrees to be hypnotized and
undergoes a formal induction must, to fulfill his role, alter his expectancies, behavior, and
view of the world. Inherent in this altered role is a decrease in critical judgment. One cannot
participate in even the simplest hypnotic suggestion (e.g., as you begin to feel a force
pulling your hands together, they will move together by themselves) without such a
decrease. Otherwise one would simply respond to such suggestions by saying “that is
absurd.” Taken together, the demands of a hypnotic role and the inherent decreased critical
judgment allow a blurring of the boundary between fantasy and memory, an increase in
certainty unrelated to accuracy, a tendency to misattribute whether information was learned
during hypnosis or before it, and a willingness to accept even a major change in memory as
credible.
Further, if a subject is relatively highly hypnotizable, the suggestions to relive events that
routinely follow hypnotic induction in the forensic context may have additional effects. First,
the frequent inclusion of confabulated, vivid detail in the new material makes hypnotically
influenced memories more credible (Dywan, 1995). Also, fantasies entirely unrelated to
what actually occurred may also be suggested during hypnosis and remembered as veridical
(Laurence, Nadon, Nogrady, &Perry, 1986). This is especially the case when there are no
clear original memories to overlay (cf. Orne, 1979 see also Karlin, 1983) or when, as in
civil cases, the hypnotized party has a strong interest in “remembering” one version of
events (cf. Karlin, 1997 Sprynczynatyk v. General Motors, 1985). Finally, more highly
hypnotizable subjects may subjectively relive events and vividly experience a version of the
past. Unfortunately, vividness has no relation to historical accuracy, but again increases
confidence inappropriately (cf. Frankel, 1994). In summary, we find a formidable basis for
automatically keeping hypnotically influenced testimony out of court.
As Mr. Hoover says, the problem in presenting this point of view at this time is both that it
1) seems rigid and 2) stands against the legal tide represented by the changes in the
