| In ancient China, a portion of rice spit from a person's | | | | interrogation. Marston firmly believed that proper |
| mouth revealed whether he or she was lying. Spitting | | | | interrogation techniques must be used along with |
| out dry rice indicated the dry mouth of a liar. | | | | technology in order to acquire accurate lie detection |
| In Europe, during the Middle Ages, torture was used | | | | results. (An interesting side note: Marston also |
| as a means of forcing a person to tell the truth. Ken | | | | created the comic book character Wonder Woman.) |
| Adler's article To Tell the Truth: The Polygraph Exam | | | | John Larson, who followed Marston's work, was a |
| and The Marketing of American Enterprise states | | | | University of California medical student and an |
| that the practice of torture was rooted in the theory | | | | employee of the Berkley police department. In 1921, |
| that "the body's agony would oblige the lying mind to | | | | Larson invented the first instrument capable of |
| croak out its secret." | | | | continuously recording blood pressure, respiration, and |
| Europe's tolerance for torture declined throughout | | | | pulse rate. The machine, which he called a |
| the eighteenth century. In the early 1700s, Daniel | | | | cardio-pneumo-psychogram, documented all this |
| DeFoe was the first to move away from torture by | | | | information on a drum of paper. To be used along |
| suggesting that deception could be evaluated by | | | | with the machine, he also developed an interview |
| monitoring the heart rate. Cesare Beccaria, in 1764, | | | | technique called the R/I (Relevant/Irrelevant) |
| wrote of torture, "By this method, the robust will | | | | procedure. His technique mixed questions relevant to |
| escape, and the feeble be condemned. These are | | | | the crime with questions that were irrelevant. This |
| the inconveniences of this pretended test of truth." | | | | was based on the theory that an innocent person |
| In 1895, the Father of Modern Criminology Cesare | | | | would have a similar physiological response to both |
| Lombroso, became the first person to use science as | | | | types of questions, while a guilty person would react |
| a method of detecting deception. Lombroso used | | | | more intensely to the relevant questions that |
| devices called the plethysmograph and the | | | | focused on the crime. |
| sphygmograph. The suspect wore an airtight | | | | Leonarde Keeler was fascinated by John Larson's |
| volumetric glove that was attached to a rubber | | | | work. He spent much of the early 1920s working to |
| membrane. This activated a pen that rolled over the | | | | understand and improve the science of lie detection. |
| surface of a smoked drum. The speed of the pen | | | | Keeler used Larson's machine as a starting point, |
| varied with the suspect's blood flow. Lombroso | | | | eventually designing a new machine that he called the |
| believed that, when a person tells a lie, the stress of | | | | emotograph. Keller added a kymograph, which |
| deception affects his or her heart rate and blood | | | | rotated the drum of paper at a regular speed |
| pressure. By observing the deviations traced by the | | | | beneath the pens. He also improved the recording of |
| pen, an investigator would see when and if the | | | | the data from the pneumographic tubes that |
| suspect was lying. | | | | wrapped around the suspect's chest and abdomen in |
| The next advance came in 1897, when B. Sticker | | | | order to measure the rate and depth of breath. The |
| developed a method of measuring the amount of | | | | biggest change Keeler installed was a |
| sweat a suspect produced during interrogation. This | | | | psychogalvanometer, the same device that B. Sticker |
| was determined by the electrical conductibility of the | | | | had experimented with in 1897, to measure the |
| suspect's skin. | | | | resistance of the skin to small electrical currents |
| The first "polygraph" machine was actually a copy | | | | emitted through metal electrodes attached to two of |
| machine invented in 1804. The name, derived from | | | | the suspect's fingertips. This last addition is what |
| Greek, means "many writings". In the very early | | | | credits Keller with creating the modern lie detector. |
| 1900s, James MacKenzie, an English doctor, invented | | | | Sometime in 1924 or 1925, Keeler's handmade |
| what he called the "ink polygraph". This was used to | | | | emotograph was destroyed in a fire. August Vollmer, |
| monitor cardiovascular responses by measuring pulse | | | | an acquaintance and chief of police at the Berkley |
| and blood pressure. | | | | Police Department, soon brought Keeler to William |
| In 1914, Vittorio Benussi used pneumatic tubing to | | | | Scherer of the Western Electro Mechanical Company. |
| study an individual's breathing rates. The device | | | | Following Keeler's written plans and instructions, |
| wrapped around the person's chest and measured | | | | Scherer developed a mechanical metal bellow, a |
| depth and rate of breath. Eugene Levitt, in his article | | | | motor drive, a pneumograph to go around the chest, |
| The Scientific Evaluation of the Lie Detector, noted | | | | and a mechanical indicator to mark the graph when a |
| that Benussi's discovery showed that the "ratio of | | | | question was asked. This new polygraph machine |
| inspiration and expiration was generally greater | | | | was then encased in a mahogany traveling case. |
| before truth telling than that before lying." This last | | | | Leonarde Keeler's patent ran out in the late 1930s, |
| discovery gave scientists the final piece of their | | | | after which time the government and private |
| puzzle; blood pressure, pulse rates, sweat production, | | | | businesses took over in further advancing the |
| and breathing rates could all be linked to the act of | | | | technology. The basic technology has remained the |
| deception. | | | | same, though the equipment is now computerized |
| William M. Marston (also known as Charles Marston), a | | | | and more sensitive. |
| psychologist born and raised in Massachusetts, | | | | The use of the polygraph remains controversial. |
| invented the true early prototype for the lie detector | | | | Physiological changes caused by emotional factors |
| machine. In 1915, Marston, with the help of his wife | | | | (guilt, fear, anxiety) can be remarkably similar to |
| Elizabeth, first demonstrated a lie detection test that | | | | those of deception. Also, poorly phrased questions |
| used a sphygmomanometer (blood pressure cuff) to | | | | can be misleading and confusing for the person being |
| measure systolic blood pressure as a means of | | | | tested. For the most part, lie detector tests remain |
| determining whether a suspect was lying during an | | | | legally inadmissible. |