Basic concepts what is Polygraphy?

Europe and Early United States (17th Century)

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Forensic Polygraphy
Europe and Early United States (17th Century) - Trial by water was commonly used on those accused of witchcraft. The accused was bound (hand and foot) and then cast into the body of water. If the accused sank, he was hauled to the surface half-drowned and deemed innocent. If the floated, he was deemed guilty and burned to death.

Detecting Lies through Observation Methods

  1. Through Facial Expression

  2. Blushing, paling or profuse sweating of forehead.

  3. Dilation of the eyes, protrusion of eyeballs and elevation of upper eyelids.

  4. Squinting of the eyes (showing envy, distrust, etc.).

  5. Twitching of the lips.

  6. Excessive winking of the eyes.

  7. Failure to look the inquirer “straight into the eyes”.

  8. Excessive activity of the Adam’s apple and the vein at the temple due to dryness of throat and mouth.

  9. Quivering of nose or nostrils.

  10. A peculiar monotone of the voice.

  11. A forced laugh.

  12. Rolling of eyeballs from one direction to another

  13. Through Postural Reaction

  14. Fidgeting, tapping or drumming of fingers on the chairs or the other surfaces.

  15. Swinging of legs or one leg over the other.

  16. Unnecessary movements of hands and feet (like scratching, nail biting, thumb or finger sucking).

  17. Pulsation of the artery in the neck.

  18. Incoherence, trembling and sweating of the whole body.

Detection through Regular Police Methods

Police methods sought to answer the legal investigative process to the following: The “five Wives and One Husband” (5 W’s and 1H) which stand for: WHAT, WHEN, WHERE, WHO, and HOW. The “Three Eyes” (3 I’s) which stands for: Information gathering – through record Check, Surveillance and Intelligence Check, Investigation – through Interrogation or Interview for Admission or Confession, Instrumention or Criminalistics (Police Sciences) with the use of the different Investigative Forensic Sciences such as Medico Legal or Forensic Medicine, Forensic Chemistry, Police or Investigative photography, Forensic Ballistics (Firearm Identification), Questioned Documents Examination, Dactyloscopy, Police or Investigative Communication, Polygraphy /Deceptography


In the middle of the 19th century, Dr. Hans Gross, an Austrian known as the “Father of Criminalistics”, defined search for truth as the basis and goal of all criminal investigations. He asserted that “a large part of the criminalist’s work is nothing more than a battle against lies. He has to discover the truth and must fight the opposite. He meets the opposite at every step.

The searches for truth and attempts at uncovering falsehood have been a universal and almost constant endeavor dating back at ancient times. In their attempt to discover deception, primitive societies developed complex procedures founded on magic and mysticism. The doors to the truth, divine creatures sent messages through fire, boiling water and torture. In some instances, faith in this powerful mysticism miraculously allowed the innocent to go unscathed while the guilty bore the mark of guilt.

Some of these rituals were based on sound physiological principles. Oriental people for example distinguished truth form lying by having the entire accused chew dry rice and then spit it out. While this was a simple task for the honest, those who were deceiving have difficulty in accomplishing this task and were then judged to be guilty and punished accordingly. This practice recognized that fear slows the digestive process, including salivation. Thus, the deceptive were unable to spit out the dry rice, while the innocent, having faith in the power of their deity to clear them of the unjust accusation, felt little fear in contrast to the guilty who know they would be discovered.

Throughout the centuries, man continued to experiment with more scientific methods in determining truth and deception with the following scientists having contributed much in the development of the polygraph instrument:

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