Since the time humans first began communicating with one another We have made up stories. We have also tried to discern these lies from reality and this was even more crucial as societies established legal systems. Police and other authorities who investigate crimes know that human ability to detect truth is limited, however we have the capability to develop technology that can identify signals that are not within our reach. It was the polygraph that is the initial invention to verify truth that demonstrated the ability of technology to spot deceit. But what is the status of this technology against the current situation?
What’s the History Behind The Polygraph
The polygraph was referred to in the form of the “lie detector” however, that is an oxymoron. There is no conclusively scientific method to identify the lies of a person, but there are methods of measuring the psychophysiological effects triggered by stress from being deceived. This idea is what has led to the development of the polygraph and later, more advanced technology for verifying truth, like computer voice stress Analyzer (CVSA(r)).
It was in 1878 that Italian scientist Angelo Mosso studied the physiological responses of people in response to questions. He used the plethysmograph device to assess cardiovascular and respiratory reactions. Others took his work and made improvements to it.
The Canadian psychologist from Canada, John A. Larson created a variant of the polygraph, while in the Berkeley (California) Police Department. The device was named by him “polygraph” after the Greek “polygraphos,” which refers to “much writing.” The device could read blood pressure and graph it as well as respiration and pulse. Leonarde Keeler further contributed to the device in 1938, by adding sensors to measure the galvanic skin responses.
The polygraph model currently in use works much the same way as the ones that were invented around 100 years ago. It measures the body’s responses using sensors in the body. They include a blood pressure cuff that measures the heart rate and blood pressure and pneumograph tubes that measure the rate of breathing, and galvanometers that are attached to the fingertips to gauge sweat.
In the 1940s, Chicago attorney John E. Reid further developed the polygraph method. Reid developed The Reid Technique, an interview and interrogation method that is widely used by law enforcement agencies with and without polygraph test.
The polygraph of today is digital, and, while it works with the same principles with the same sensors and premise as an analog one that it utilizes an algorithm to analyze the data and display it in a computer software.
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Polygraph Vulnerabilities
Chicago attorney William Scott Stewart wrote an article within the issue of November 1941 in Esquire Magazine titled “How to beat the”Lie Detector.” It is likely to be the first piece focused on countermeasures for the polygraph. Stewart noted that you could alter the results of the polygraph by increasing your feelings when you are asked innocent questions. These “control inquiries” are typically asked at the time of the Control Question Test (CQT) and are designed to provide comparisons to the pertinent questions. In terms of physical countermeasures Stewart advised biting the tongue or the inside of the mouth, or performing muscle movements that aren’t visible by the person who is performing the action like the toe moving or flexing an ankle muscle.
The polygraph is still susceptible to psychological as well as physical countermeasures. It has a high error rate that is based on inconsistent, false positives or false negatives.
Manipulation in Control Questions:
Subjects are able to manage their breathing
Sphincter muscles contract
Or inside the mouth
The thought of horrible things
A former polygraph examiner as well as Oklahoma City Detective Sergeant Doug Williams was sentenced to two-years in jail by federal authorities in the year 2015 for activities related to teaching people to beat the polygraph. After many years of using the technology, he started to doubt its results and instructed hundreds of people to employ methods to counter the polygraph. Williams rates its accuracy as 50 percent or more. In actual fact, U.S. government agencies have trained individuals who participate in undercover investigations to defeat the polygraph, which is a confirmation of Williams claims that strategies are taught in order to beat the polygraph.
Manipulation During Relevant Questions
Practicing relaxation techniques
Mental calculations
The thought of calm subjects
The Positive Effects of the Polygraph
Despite its shortcomings, the polygraph set a new benchmark in the use of truth-verification technology in the process of police interviews and set the stage for the future of innovations. The polygraph community is an influential lobby and faithful users. A lot of examiners who have been who are trained to use this technique are hesitant to upgrade their abilities or invest in more advanced technology however, approximately thirty percent of the most popular polygraph research studies reveal that this truth-checking tool isn’t as reliable as people would prefer to believe. There are a variety of results that measure the quality of the polygraph with estimates that range between 70 and 90 percent accuracy. Additionally only 29 percent from 194 “scientific studies” that were cited as proof by advocates of the polygraph meet the standards for scientific quality, as per The 2003 National Research Council report by the Committee to Review the Scientific Evidence regarding the Polygraph.
Evidence from polygraph forensics is accepted in court. 19 states permit polygraph testimony that is based on specific conditions for every state. The technology is also utilized for pre-employment screenings in both the private and public sector. The primary benefit to the use of the polygraph may be used to obtain confessions following examinations in cases where the subjects feel that deceit has been discovered. In the present Internet Age, individuals who are subjected to polygraph tests are able to access information on the polygraph that was previously not accessible and, in certain instances not available to the public.