28 states prohibit the introduction of a polygraph as evidence while 18 limit the admissibility

Alfonso Gambone
Connect with me
A Philadelphia criminal defense attorney representing accused persons throughout Pennsylvania and New Jersey.

Recently, my colleague, Rick Collins, Esquire, entered his appearance on behalf of professional bodybuilder and current Mr. Olympia, Shawn Rhoden to defend rape allegations following an alleged incident which occurred on October 12, 2018 in Salt Lake City, Utah. Following these allegations, Rhoden allegedly passed a polygraph test (aka lie detector), during which he was interviewed about the incident. Since that occurred, many of our readers have asked about the admissibility of polygraphs in Pennsylvania and New Jersey, where our criminal defense law firm practices and represents individuals charged with a variety of offenses including the illegal possession of narcotics, drugs, handguns, firearms, and drunk driving.

When Is a Polygraph Admissible in a Criminal Court in Pennsylvania or New Jersey?

While Rhoden passed the test, Utah, like Pennsylvania and New Jersey, generally prohibits the admissibility of polygraph results into evidence at a criminal trial unless there is a stipulation by both the prosecution and the defense. The main reason behind this is that the tests are considered unreliable as the results are based on factors which measures physiological responses such as anxiety.  Twenty eight (28) states prohibit the admission of a polygraph test as evidence while eighteen (18) limit the admissibility to only those cases where both parties stipulate (agree) to its use. This stipulation, however, would hardly ever occur because evidence that a person passed or failed a test would substantially damage or hinder either the prosecution or defense argument. Utah is one of the states which permit the admissibility of the polygraph where both parties agree and it will be interesting to see if the prosecution in the Rhoden’s case agrees to a stipulation.

How Do Polygraphs Work?

While the results of the test are considered inadmissible with some exception, it’s important to keep in mind that many law enforcement agencies, along with local district attorney offices, and even US attorney’s offices utilize this technology. While courts have taken issue with its reliability, the instrument itself tests 3 systems within the human body through convoluted rubber tubes which are placed over the examinees chest and abdominal area to record respiratory activity, small metal plates attached to the fingers which record sweat gland activity, and a blood pressure cuff to record cardiovascular activity. While a polygraph is sometimes referred to as a lie detector, it does not tell if a person is lying, but only that there was a physical response to a question which could indicate truthfulness.

False Positives vs. False Negative Errors

Courts consider polygraphs unreliable and errors are referred to as either false positives or false negatives. A false positive occurs when a truthful examinee is reported as being deceptive and a false negative occurs when a deceptive examinee is reported as truthful. There is no conclusive data on which occurs more often and examiners use a variety of techniques and procedures to limit these errors including the following:

  • An assessment of the examinees emotional state
  • Medical information about the examinees physical condition
  • Specialized tests to identify overly responsive examinee
  • Control questions to evaluate the examinee response
  • Factual analysis of the case information


New Jersey & Polygraph Admissibility

Similar to Utah, New Jersey is one of those states where parties (prosecution and defense) can agree to the admissibility of the polygraph as courts in the Garden State have ruled that a polygraph test have sufficient probative value and are therefore admissible where both parties agree. If parties stipulate, it must be clear, unequivocal and complete.  The stipulation must be entered into with full knowledge of the right to refuse and the consequences involved in taking it. Finally, he examiner must obviously be qualified and the test be administered in accordance with established polygraph techniques.


For more information on the best criminal defense strategies in Pennsylvania and New Jersey, please keeping reading this blog, watch my videos and download one of my free books.  

Be the first to comment!
Post a Comment