The Admissibility into Evidence of Polygraph Test Results
The recent court opinion from the Dallas, Texas, Court of Appeals ( Leonard v. Texas), which decided that polygraph test results are admissible evidence in a probation revocation hearing, is both good and bad for the citizen-accused. It is good for one charged with a crime, for example, who can now present polygraph evidence to a judge that he did not consent to the entry of a police officer into his apartment to search it, even though the officer testifies that he had permission from the accused to enter the apartment. Similarly, it is good for a citizen-accused who can present polygraph evidence to a grand jury to show that the allegations against him/her are not true, and that he/she should not be charged with a crime based on those false allegations. (However, polygraphs have usually been submitted to grand juries without objection in the past in Texas.) The case did not hold that polygraph evidence is admissible in a jury trial, only in a probation revocation hearing held before a judge. However, the next logical step would be for attorneys to try to persuade a judge to admit polygraph evidence in a jury trial.
The court decision is bad for the citizen-accused because polygraphs are only as reliable as the polygraph operator; and, therefore, in the words of one former president of the American Polygraph Association, depending on the skill of the operator, a polygraph result can be "a flip of the coin." Polygraphs are often unreliable for at least two reasons: 1) The subjectivity of the operator, including the type of polygraph test the operator selects, the skill level of the operator who grades the test results (the charts), etc., and 2) the inescapable risk of simple human error in communication caused by the almost infinite variety of culturally based nuances in all languages (including English), that are inherently involved when one human questions another and must interpret those answers.
For example, that same former president of the American Polygraph Association, referenced above, gave, a few days apart, the exact same polygraph test twice to this attorney's client with contradictory results. The first time the client failed the test; the second time the client passed it. The client was accused of fondling his 15-year-old niece. After he failed the first polygraph test, this attorney confronted the client and accused him of lying. The client adamantly professed his innocence, but he said that he had taken cocaine a little while before he had walked into the TV room where his niece was; however, he had not told (and he had not been asked by) the polygraph examiner about taking any drugs or other substances.
After the client failed the first test, this attorney asked the well-regarded polygraph operator (who had administered the first test) whether the client's omitted disclosure could have caused the client to flunk the test. The response of the polygraph operator was, "Arch, the test just shows whether there is deception or not, not the reason for the deception." The operator agreed to (and did) re-test the client for free; this time, however, the client disclosed to the polygraph operator the fact that he had taken cocaine on the night of the accusation. The client passed the test. This client was Hispanic, he could not afford an attorney, and the Catholic priest of this attorney's church had asked this attorney to represent the man because the priest had thought that he was innocent. Unfortunately, after the first polygraph test, most criminal defense lawyers, even good ones, would have concluded, just as the competent polygraph operator did, that the client was guilty, without further inquiry. This one, simple example, however, shows the very real limits of a polygraph in determining guilt or innocence – Scary, isn't it?
On the other hand, consider this case: An innocent man, age 30, was wrongfully convicted and sentenced to two consecutive life sentences for an offense he did not commit. His original defense lawyer had assumed (without good reason) that the innocent man would plead guilty, so the defense attorney did not prepare for trial. After being convicted and sentenced to two consecutive life sentences, under Texas law, the innocent man would have never been released from prison. That is, no parole was legally possible. After four years, this defense attorney was hired to investigate the possibility of a post-conviction application for a writ of habeas corpus, based on evidence of innocence that the original defense attorney did not bother to learn about, because he did not investigate the case. The District Attorney also wanted the client to take a polygraph test.
However, a proper polygraph requires a baseline of guilty reactions from the subject, to questions that create a guilty physiological response (quickened heart beat, etc.). A typical question, for example, is, "Have you ever fudged on your income tax returns?" The problem with a question like that is that a person in the position of the innocent man, with absolutely no prospect of ever being reunited with his family, doesn't care any longer about something like income taxes. So he does not have a guilty reaction to such questions. What questions would you propose to ask the man to establish a baseline of guilty reactions to compare with the relevant questions related to the actual offense?
After the baseline was established and the test was given to the client, in order to strengthen the impact of the polygraph with the law enforcement authorities, this lawyer, whose client had substantial resources, sent the polygraph test results to two other polygraphers in two other states, who had outstanding reputations. The polygraph charts were to be graded "blind," without the additional polygraphers knowing the client's name, the original grades given to the test results or anything else about the case, except the questions, the answers and the charts. When all three examiners passed the client and determined that there was "No deception," the impact of the polygraph was enhanced and was very helpful in freeing the client, combined with a very thorough investigative due diligence, over a period of nine months, that uncovered evidence showing the client's innocence that had not been presented by the defense counsel and that could have made a difference in the outcome of the case.
The original defense lawyer was found to have failed to render "effective assistance of counsel," a right guaranteed to all people in the United States (including non-citizens) by the Sixth Amendment to the U.S. Constitution, as made applicable to the states by the 14th Amendment to the U.S. Constitution. In this case, based on all of the above, the result was a new trial for the innocent man, after which he was freed and went home to his loved ones. A polygraph run by and confirmed by competent polygraph operators, the administration of which is monitored closely by the criminal defense lawyer, can have a substantial impact on the results in a criminal case, including a post-conviction application for a writ of habeas corpus.