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The present study also examined the ability of highly trained polygraph examiners to detect the use of countermeasures. The results of this study indicate that they cannot detect the use of spontaneous [i.e., untrained] countermeasures. Their ratings of the likelihood of countermeasure use were generally unreliable and were not associated with actual countermeasure use at better than chance levels. Field polygraph examiners generally appear to operate under the notion that a detection of countermeasure attempts is synonymous with attempted deception to the relevant questions of the examination... Clearly, that notion is incorrect. The results of this study show that an examiner's decision of countermeasure use is unrelated to both countermeasure use, and to deception. Our analyses indicated that almost half of the subjects judged to be using countermeasures were in fact Innocent subjects. These results strongly suggest that the field practice of equating countermeasure attempts with deception to the relevant issues of an examination should be abandoned.