History

History of polygraph

Founding fathers | History, and evolution, of the instrument

History of polygraph cannot be explained without a small prelude about Detection of Deception. The polygraph instrument is a result of decades even centuries of the search for truth.

We will try to give a brief introduction into detection of deception and the polygraph instrument within this field.

History of the detection of deception/Finding truth through deception

Polygraph InstrumentThe detection of deception started as soon as an organized intent on having a fair society arose. Many writings have been discovered on archaic ways to detect if somebody was telling the truth. For instance, in West Africa persons suspected of a crime were made to pass a bird’s egg to one another. If a person broke the egg, then he or she was considered guilty. (They were too nervous to control their movements).

In Ancient China, during a prosecutor’s speech, the suspect held a handful of rice in his or her mouth. Since salivation was believed to cease at times of emotional anxiety, the person was considered guilty if by the end of that speech the rice remained dry.

Forensic science is a scientific method of gathering and examining evidence and polygraph is an integral part of Forensic science. Crimes are often solved with the use of examinations that gather fingerprints, palm prints, footprints, tooth bite prints, blood, hair and fiber samples. Handwriting and typewriting samples are studied, including all ink, paper, and typography. Now polygraph has become a cost effective method in the selection or elimination of suspects/witnesses as well as an important interrogation tool.

In the 1248 Chinese book Hsi DuanYu or the Washing Away of Wrongs, ways to distinguish between death by drowning or death by strangulation were described.

Italian doctor, Fortunatus Fidelis is recognized as being the first person to practice modern forensic medicine, beginning in 1598. Forensic medicine is the “application of medical knowledge or science to legal questions.” It became a recognized branch of medicine in the early 19th century.

The history of the polygraph instrument

An earlier and less successful lie detector or polygraph was invented by James Mackenzie in 1902.

However, the modern polygraph instrument was invented by John Augustus Larson in 1921 and was later improved upon by Leonard Keeler between 1930 and 1940, the “Compact Keeler Polygraph“. Regardless of the advancements in the field, the concept behind the “Compact Keeler Polygraph” remains. The same readings are nowadays recorded but now in a digital format.

Polygraph componentsStoelting released the worlds first all electronic polygraph in 1974. The Stoelting Polyscribe.

With the arrival of the Computer Aided Polygraph System in 1988 and the Computerized Polygraph System in 1992, the polygraph entered the digital age. This brought about unprecedented accuracy, as well as, flexibility.

Nowadays the polygraph instrument can easily be transported and set up in almost any location, as far as privacy and silence are guaranteed.

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