Assessment of Polygraph Validity Considering Ruby’s Mental State
An accurate evaluation of Ruby’s polygraph examination depends on whether he was psychotic. A psychotic individual, being divorced from reality, might believe a false answer to be true and therefore not register the emotional response characteristic of deception that a normal person would. If a person is so mentally disturbed that he does not understand the nature of the questions or the substance of his answers, no validity can be attached to the polygraph results. Herndon stated that a person in touch with reality could be evaluated by the polygraph like any other examinee. Based on his prior contacts with Ruby and on observing him throughout the polygraph proceeding, Dr. William R. Beavers testified that in the greater proportion of Ruby’s answers, he appeared aware of the questions, understood them, and gave answers based on an appreciation of reality.
CAPÍTULO II. With the assistance of Agent in Charge Sorrels of the
Chapter II examines the circumstances surrounding the polygraph examination of Jack Ruby, focusing on Dr. Beavers’ psychiatric diagnosis, Herndon’s polygraph interpretation, and the Commission’s handling of the results. The chapter also includes Appendix XVIII with citation conventions and a Foreword.
Dr. Beavers’ Psychotic Depressive Diagnosis of Ruby
Dr. Beavers stated that he had previously diagnosed Ruby as a “psychotic depressive,” establishing the psychiatric baseline that would shape the subsequent polygraph analysis.
Herndon Testimony on Polygraph Invalidity Given Ruby’s Diagnosis
Based on the assumption that Ruby was a “psychotic depressive,” Herndon testified that there would be no validity to the polygraph examination and that no significance should be placed upon the polygraph charts.
Herndon Testimony on Polygraph Interpretation Assuming Mental Competence
Considering other phases of Dr. Beavers’ testimony, Herndon stated that, based on the hypothesis that Ruby was mentally competent and sound, the charts could be interpreted to indicate that there was no area of deception present with regard to his responses to the relevant questions during the polygraph examination.
Dr. Beavers’ Exceptions for Polygraph Questions on Family and Counsel Safety
While stating his opinion that Ruby was in touch with reality and understood the questions and answers, Dr. Beavers excepted two questions where he concluded that Ruby’s underlying delusional state took hold. Those questions related to the safety of Ruby’s family and his defense counsel. Ruby had answered these questions in the preliminary session by stating that he felt his family and defense counsel were in danger, but he did not answer either question when the polygraph was activated. Dr. Beavers interpreted Ruby’s failure to answer as a reflection of “internal struggle as to just what was reality.”
Dr. Beavers’ Testimony That Polygraph Test Was Not Injurious
Dr. Beavers testified that the polygraph test was not injurious to Ruby’s mental or physical condition.
Commission Approval of Ruby’s Requested Polygraph Examination
Because Ruby not only volunteered but insisted upon taking a polygraph examination, the Commission agreed to the examination.
J. Edgar Hoover’s Statement on Polygraph Limitations
FBI Director J. Edgar Hoover commented on the polygraph examination, noting that the polygraph is not in fact a “lie detector” but is designed to record emotional responses in the form of physiological variations which may indicate and accompany deception. The FBI felt that the polygraph technique is not sufficiently precise to permit absolute judgements of deception or truth without qualifications, and noted that one of its limitations relates to the mental fitness and condition of the examinee to be tested.
Dr. Beavers’ 1964 Dallas Testimony on Ruby’s Condition and Polygraph Nonconclusiveness
During the proceedings at Dallas, Texas, on July 18, 1964, Dr. William R. Beavers, a psychiatrist, testified that he would generally describe Jack Ruby as a “psychotic depressive.” In view of the serious question raised as to Ruby’s mental condition, no significance should be placed on the polygraph examination and it should be considered nonconclusive, as the charts cannot be relied upon.
Commission Publication of Polygraph Hearing and Operator Deposition Transcripts
Having granted Ruby’s request for the examination, the Commission is publishing the transcript of the hearing at which the test was conducted and the transcript of the deposition of the FBI polygraph operator who administered the test.
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