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(b) Delayed recall?
(c) Delayed recognition?
Plot these data on a bar graph. Use different shaded bars for the two experimental conditions.
Recall
Frequenc
y
Memory Measure
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DETECTING GUILT AND DECEPTION
OBJECTIVES
1. To analyze the various behavioral indicators of an individual’s guilt feelings.
2. To collect different kinds of data from the same subjects, both quantitative (reaction time) and
qualitative (word associations and expressive reactions).
3. To combine these multiple sources of evidence in order to draw inferences about the guilt or
innocence of two (role-playing) suspects.
4. To consider how emotional arousal and unconscious motives may affect behavior.
5 . To raise questions about practical issues in jury decision making and the use of lie detectors in
courts and business.
OVERVIEW
“Detecting Guilt” is designed to involve the whole class in psychological detective work on a problem with
both practical implications and broad conceptual significance. The demonstration casts students in the role
of jurors who must decide the guilt or innocence of two criminal suspects. To do so, they must utilize a
variety of behavioral indicators of emotional disturbance, including word associations, reaction times, and
expressive behavior.
1. Begin by asking students to mention something that made them feel very guilty in the past (in
elementary, junior high, or high school).
2. Have them try to come up with a definition of guilt.
3. Ask them what are the negative consequences and positive effects of guilt, analyze the common
elements, and list their answers to the questions.
4. Briefly contrast the conscious and unconscious forms that guilt may take (the student examples are
likely to be conscious instances).
5. Relate the discussion back to the memory analysis of the previous week (if you did that
demonstration) by having students consider the effects of guilt on memory.
6. Ask the students if they were ever in a situation in which they felt guilty over some misdeed but
were able to conceal their guilt from the critical appraisal of some “judge.” How did they mask their
feelings?
7. Conduct the demonstration in which one subject role-plays feeling guilty about a crime while
another subject is an innocent person who is also a criminal suspect; the rest of the class engages in
the task of “psychodetection.”
GENERAL INTRODUCTION
Our working definition of guilt is a (1) negative (2) emotional and/or cognitive condition based on the (3)
belief that one (4) could have emitted a response that would have led to (5) significantly better consequences
for some (6) social agent than the response actually performed.
1. This excludes emotions based on power or revenge.
2. Guilt may be associated with anything from extreme arousal to minimal arousal but is always
based on one’s interpretation of a social situation that involves the individual.
3. This excludes most nonhumans from feeling guilt.
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4. “Could have” behaviorally as well as physically, which excludes those who tried their best and
failed.
5. This excludes cases in which the differences in consequence between two responses are minor and
stresses that guilt is based on a personal judgment.
6. This means that if the social agent discovered what was done or withheld, he or she would be
distressed.
PUBLIC INTERROGATIONS
In attempting to determine whether a suspect is guilty or innocent, police interrogators often rely on
emotional indicators of self-betrayal. One manual, written by Inbau and Reid (1962) and used to train
detectives, proposes the following symptoms as signs of guilt:
1. Pulsation of carotid artery in the neck.
2. Excessive activity of the Adam’s apple.
3. Looking at floor or ceiling rather than looking the interrogator “straight in the eye.”
4. Swinging one leg over the other, foot-wiggling, wringing of the hands, tapping with the fingers, picking
fingernails, etc.
5. Dryness of the mouth.
6. Swearing to the truthfulness of assertions.
7. Saying “I have a spotless past record” or “I’m a religious man.”
8. Saying “Not that I remember.”
(See Inbau, F. E., & Reid (1962). Criminal Interrogation and Confessions. Baltimore: Williams & Wilkins.)
THE POLYGRAPH
The dynamic role that emotion plays in influencing human behavior is often obvious from changes in the
individual’s behavior such as those suggested above, but perhaps the most characteristic indicator of
emotion is widespread visceral activity within the person. Several such visceral changes can be monitored;
the well-known lie detector (polygraph) takes measures of electrical skin conductance (GSR), heart rate,
respiration, and sometimes other changes such as indices of the emotional effects of “neutral” stimuli
versus “critical” stimuli associated with the crime. As Inbau and Reid have said, “An offender who is led to
believe that his appearance and demeanor are betraying him is thereby placed in a much more vulnerable
position. His belief that he is exhibiting symptoms of guilt has the effect of destroying or diminishing his
confidence in his ability to deceive and tends to convince him of the futility of further resistance. This
attitude, of course, places him much nearer the confession stage” (p. 29).
The polygraph technique assumes that liars are aware of their lying and will experience measurable
emotional reactions as a consequence. Polygraph lie detection is a psychological test of questionable
psychometric merit.
A laboratory study (comparable to the one you will conduct here) showed polygraph examiners quite
fallible. Fifteen students individually participated in a theft of money from an office, while 15 were innocent
of this staged “crime.” Six polygraph examiners knew that half the suspects had stolen something and half
had not, but they were not able to determine accurately which ones were guilty. The false alarm rate ranged
from 18 to 55 percent. That is, even the best interpreter judged 18 percent of the truthful innocent subjects to
be lying, guilty suspects!