Polygraphs Introduction Homo Sapiens have yearned for a reliable and consistently correct way of finding out if one is telling the truth since ancient times. Early societies used torture. Statements made by a person on the rack were considered especially believable. (Jussim, pg.65) There was also trial by ordeal, which was based on superstition. For instance, if there were two suspects for one crime, it was thought that the innocent would be stronger in combat and thus vanquish a guilty opponent. This example shows how it was done long ago.
The ancient Hindus made suspects chew rice and spit it into a leaf from a sacred tree. If they couldnt spit, they were ruled guilty. Although this procedure long predated the modern lie detector, it was based-knowingly or not- on assumptions about psychological stress much like those that support polygraph examinations today. The ancient test depended on the fact that fear makes the mouth dry, so rice would stick in a guilty persons mouth. For the procedure to work, the subject had to believe in its accuracy and, if guilty, had to be anxious about being caught in a lie.
(Ansley, pg. 42) The modern polygraph is said to measure the subjects internal blushes in much the same way. It does not really detect lies-only physiological responses. The theory behind the polygraph is that lying always heightens these responses. When taking the test, subjects are hooked up to a briefcase-sized machine by means of several attachments. usually, a pneumatic tube goes around the chest to measure respiration, a cuff squeezes one bicep to monitor blood pressure, and electrodes are attached to two fingertips to determine the skins resistance to electrical current (which is related to how much the subject is sweating).
An examiner, or polygrapher, quizzes the subject. As the subject answers the questions, the machine draws squiggles on a chart representing physiological responses, which are supposed to clue the examiner in to the subjects lying, or truthful, ways. Just as the ancient Hindu was betrayed by a dry mouth the modern polygraph subject is said to indicate that he or she is lying by breathing harder or having a racing pulse. (In arriving at a conclusion about a persons deceptiveness, some polygraphers also use their own subjective observations of the persons behavior.) The test will not work, though, if the subject does not believe in the procedure. If the subject doesnt not think the machine can tell the examiner anything, then he or she wont be anxious and wont show the heightened responses that the machine is designed to record.
Because of this, the examiner will often use deceptive tricks to impress the subject with the polygraphs alleged accuracy. Modern polygraphy got its start in Chicago in the 1930s, where it was used in criminal justice investigations. Now it has a wide range of other applications, including screening job applicants and employees, conducting intelligence investigations in federal security departments like the Central Intelligence Agency, and trying to uncover the source of unauthorized disclosures to the press of government documents or information. The strategies used by polygraphers vary from one application of the machine to another. in pre-employment screens, subjects are typically asked a series of about twenty questions.
Irrelevant questions like Is your name Fred? serve to put the subject at ease. Typical relevant questions are: have you ever been convicted of a crime? Stolen from a previous employer? is all the information on your employment application correct? Do you take illegal drugs? This series is repeated, and if physiological responses to particular relevant questions are constantly and significantly higher than responses to others, the subject is reported as deceptive. Investigations into specific incidents are more complicated. Tin these, relevant questions concern only the alleged wrong doing-for instance, Did you steal the missing $400? To determine truthfulness, polygraph responses to these questions are compared with responses to other questions- called control questions-that are provocative but do not relate to the incident. The use of polygraphs in the work place greatly increased over the last fifteen years, and now over two million of them are given annually in the United States. Seventy-five percent of them are administered to job applicants.
Other tests are given periodically or randomly to employees or as part of an investigation in the wake of a theft or act of sabotage. Although subjects technically submit to testing voluntarily – generally signing a release saying they are willing to undergo such an examination- they actually have few options. Applicants who refuse a screen are not likely to be hired, and even long-time employees who refuse risk being fired or having their decision held against them in some way. According to the American Polygraph Association (APA), an industry group that promotes lie-detector use, one-fifth off all major U.S. businesses use the machine in some capacity. The test is most commonly used by firms in which low-level employees handle large sums of cash, such as bans and department stores. But all kinds of concerns have tested their employees- from meat-packing companies to hospitals.
Though some companies have in-house polygraph operations, most hire a security firm to do the lie detection for the. Generally, companies using lie detectors make submission to testing a condition of employment. Polygraphs are also sometimes used on state and federal government employees. The Department of Defense (DOD) uses the polygraph more than any other federal agency except the CIA and the National Security Agency (NSA). The DOD gave 25,000 tests in 1985.
The department uses polygraphs for criminal and counterintelligence investigations and to screen people being considered for access to classifies information. The CIA and NSA, which together have about 100,000 employees, screen all job applicants with the machine and also use it in investigations as well as in random checks on employees. No one refusing a pre-employment polygraph will be hired by the CIA or NSA. In 1979, three-quarters or more of the applicants turned down for CIA jobs were rejected because of their polygraph results. Sometimes the federal government also uses lie detectors to track down the source of unauthorized disclosures, or leaks, to the press. The U.S. Postal Service uses the polygraph more than any other agency not involved in national security. The primary use here is in investigations of mail theft.
The Office of Personnel Management strictly regulates pre-employment polygraph programs for many federal agencies. Its rules require that any agency doing screening have a mission approaching the sensitivity of that of the CIA. The questions asked in the course of the exam must be narrow, and the agency involved must monitor procedures to prevent abuses or unwarranted invasions of privacy. The rules also require employers to tell the subjects that they have a privilege against self-incrimination and a fight to consult a lawyer before the test, and, in addition, that refusal to submit to a lie detector will not be recorded in employment files. The Defense Department has similar regulations governing polygraph use. Defense employees can refuse lie detectors used in investigations of criminal activities or unauthorized disclosures without suffering adverse consequences.
The Case For The Polygraph In 1976, a southern California commercial bakery was in a bad fix. The retailers who bought its bread were finding pieces of glass and wire in the product, and they were furious. Company officials suspected sabotage. Desperate, they hired Intercept, a Hollywood company specializing in lie detection. Twenty-four hours after two polygraphers arrived, the bakery was back to normal. In the course on an examination, a long-time employee owned up: Angered at being passed over for a promotion, he had done the vengeful deed.
(Lykken, pg. 82) In 1978, a gas station in Salt Lake City, Utah, called in Polygraph Screening Service to examine its workers. Two hundred and ninety two dollars in cash had just been discovered missing, and the company had lost another $700 in cash and goods over the preceding month. During a pretest interview-the interview that examiners often give just prior to hookup with the polygraph- a worker confessed to charging customers for gas and then keeping the money instead of ringing it up on the cash register. After this worker was connected to the machine, his charts indicated strong response to queries regarding the missing $290.
He subsequently admitted that he had absentmindedly left the key in the cashbox during a trip to the bathroom. When he next checked the box, the money was gone. These examples, taken from th …