The lie detector—or polygraph machine–was first created by john Augustus Larson (1892-1965), a part-time employee the the Berkeley Police Department who was earning his Ph.D. In physiology in ~ the college of California in ~ Berkeley in 1920.

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In examining interrogations taking place in the police department, Larson came up through the principle for a device that listed nervousness as indicated by alters in blood pressure and respiratory and also pulse rates once a human was experience questioning. In the early 1920s, Larson produced a technique for recording this info on a rolling north of file so a permanent record can be created and evaluated.

The check out of Polygraphs Today–a special Note

Note: number of readers have remained in touch to tell around their difficult experiences with polygraph machines. While mine complete article explains the controversy surrounding this “lie detectors,” i feel it’s appropriate to add this details near the optimal of the article.

Polygraph makers are now considered “pseudoscience.” Authorities to compare them to phrenology (the study of bumps on the person head) or graphology (the research of handwriting), in terms of reliability—in other words, not scientifically reliable.

As that happens, the usage of polygraph machines has been deemed illegal for use in private industry. Ironically, the federal government and also many branches of criminal government still usage them.

People with any sort of anxiety disorder are unlikely to carry out well with a polygraph exam, and also conversely, human being who are determined to “beat the system,” can regularly train us to do well enough when questioned.

The story behind exactly how the “lie detector” came about seems worth telling, yet I would certainly be remiss if i didn’t acknowledge the readers that have gained in touch to define how false readings on this unreliable devices have developed serious injury in their resides through anything from denial the a task to personal embarrassment. This added information is come clarify that my write-up is not fostering the use of this devices.


To record a person’s response when the heart is contracting (what provides the systolic measure), Marston used a an easy blood press cuff and a stethoscope, recording the heart rate complying with each question. He would then keep in mind each reading as that occurred. It was a time-intensive, industrious process.

He began experimenting through this procedure in 1915, and also it to be the very first time a systematic method was supplied to detect truthfulness or deception. Later on Marston experimented v making different use of a pneumograph to document respiration cycles. (Marston is perhaps far better known together the creator of Wonder Woman, written under his pen surname Charles Moulton.)

Larson observed that there necessary to be a less laborious technique for record blood pressure and respiratory and also pulse rates.

Polygraph Patent visited Leonarde Keeler


Because Larson never ever filed for a patent, this to be left come Leonarde Keeler (1903-1949), a fellow who worked under Larson and also saw ways to make an ext improvements come the polygraph machine.

Keeler grew up in Berkeley and began visiting the police department as a teenager. He obtained to recognize John Larson, who took that on as an apprentice. As soon as Keeler came to be a permanent employee, he started to test methods to make the maker better. Because that example, the original polygraph compelled 30 minute of ready to set it up for questioning. The was burdensome, and also so was the use of the smoky document which then had actually to it is in shellacked if the results were to be preserved. Keeler come up through a means that consistent ink might be supplied so the shellacking to be no much longer necessary.

Keeler dubbed the device he developed the “Emotograph,” and also he was the very first American to obtain a patent ~ above what is commonly known as the polygraph—or lied detector device. That filed because that the development in 1925 and also the patent was granted in early 1931. In the patent application, the device is described as the “apparatus for recording arterial blood pressure.”

Unfortunately, the Emotograph was damaged in a fire, but Keeler reapplied himself and also began developing a new machine. This time he was either employed by or received capital from west Electro mechanical Company. The firm then successfully manufactured and also sold the products to police departments roughly the country.

Keeler walk on to found a polygraph institution in Chicago, the Keeler Polygraph academy (1948). In addition to running the school, he ongoing to occupational as a consultant in the field for the rest of his life.

Controversy end Polygraph Results


Today polygraph machines employ computerized program to assist with the orchestration of the test as well as the evaluation of the results. Yet no matter just how these makers are made or operated, there has been one constant argument: carry out they work-related or not?

The American Polygraph Association claims accuracy rates of over 90 percent but this is debated by many scientists. A polygraph machine, in essence, records some kind of emotionally arousal. Critics point out the this can encompass fear and also anxiety and also a host of other thoughts and also emotions.

Ironically, the one significant employer who still counts on polygraph testing is the U.S. Government. Together of 2013, about 70,000 task applicants every year undergo polygraph testing by the commonwealth government.

Critics also suggest out that there are countless books and online courses that show world how come “beat the system,” do the check less beneficial if someone has actually read up on exactly how to change the results.

However, the American Polygraph association still states that there are strong benefits to polygraph screening. The organization contends that project applicants are much more honest in completing applications as soon as polygraphing is component of the process. ~ above a mental level, this definitely makes sense. If a candidate thinks the he or she can get caught in a lie, climate the person is much less likely to lie. That said, the movie critics have enough data behind them the it is daunting to expropriate the insurance claim that the accuracy that the experimentation ranged between 86%-100%. (There room so numerous variables in environment and also test-giver and also composition of the concerns that that is very challenging to recognize how regular results deserve to be guaranteed.)

At this point, scientists would say that we execute not yet have actually anything that have the right to offer a 100 percent guarantee of human being honesty, however one point we know—inventors will save trying.

To read more stories of regulation enforcement, read around Alice Wells, one of the first female policewomen.

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Side Note: In articles around Thomas Jefferson, the is sometimes stated that he offered a polygraph machine. Throughout his lifetime, a polygraph device was actually a letter-copying machine; Jefferson’s maker saved the from having actually to re-write letters that required to be sent to many people. The alone to be a remarkable development for the time, but it is a various invention from the maker that documents heart rate or blood pressure.