Pioneers of polygraphy | Development of the polygraph instrument

Polygraph history started long before the first instrument was assembled in 1921. Discovering truth, detecting deception, has been a quest that has been pursuit by just societies throughout centuries.
Different methods were developed to detect the “liar” so that justice could be made. Although not always very scientific, these methods were designed because experience had shown that humans were not really willing to participate in solving cases. The severity of punishments were often a deterrent for individuals to contribute to the truth.
An example of such a method is the “TRIAL BY COMBAT”.
This test is thought that some supernatural influences determine the fight in favor of the fighter who had truth on his side. Although the test was used for combat in the Roman and Greek empire, this was not abolished in England until 1891.
It’s in the 20th century that the polygraph instrument was actually invented. The device has improved considerably and is nowadays an instrument used all over the world.
Pioneers of the polygraph instrument, history of polygraph instruments
John Larson
The first polygraph instrument that could be called as such was assembled by John Larson in 1921. Yes, that is right, the polygraph exists for more than a century.
The instrument that John Larson invented was a rudimentary apparatus that combined two psychophysiological channels, breathing and cardiovascular activity.
This mechanical apparatus could simultaneously register psychophysiological activity of the respiratory and cardiovascular organs.
Leonarde Keeler

Leonarde Keeler built on the polygraph instrument invented by John Larson and later added a third psychophysiological channel, the Elector-dermal activity sensor. This happened around 1938.
The actual polygraph instrument still uses these main three components to measure psychophysiological activity.
John Reid

John Reid added another device that also makes part of current polygraph instruments, a movement sensor. This sensor however is not designed to measure any psychophysiological activity but rather voluntary or involuntary movements that can influence psychophysiological data.
Polygraph manufacturers
Little by little companies started to become interested in the marketing of such devices due to an increase application. A logic step was that industrial manufacturers started to produce polygraph instruments for their industrial commercialization.
Manufacturers like Stoelting, Lafayette started to manufacture and sell to the broader public electronic and later digital polygraph instruments.
Nowadays, polygraph instruments are digital in a majority of cases and can be easily transported and used. This has helped develop the application of polygraph exams all over the world.
At Polygraph Turkey we use the latest and modern P.O.L.A.R. P1 polygraph Instrument.