It might surprise you that the first polygraph wasn’t invented to detect deception in law enforcement interrogations. The first “polygraph” came from the mind of Dr. James MacKenzie, a Scottish-born cardiologist.

MacKenzie built his device for use in the medical diagnosis of cardiovascular disease. His invention debuted to the world in 1901, and, ironically, MacKenzie coined the term “polygraph” to describe his new device.

So, if polygraph machines were originally medical devices, how did they end up in use in law enforcement? Who were the people responsible for using it in law enforcement applications, and is the polygraph a legitimate and accurate device?

 

Cesare Lombroso – The Early Beginnings

The story of the polygraph and its use in law enforcement operations starts with Cesare Lombroso in the late 1800s. Lombroso founded the Italian school of positivist criminology, arguing that criminal minds are inherited. Lombroso stated that he could identify possible criminals through their facial features.

As the self-proclaimed founder of modern psychiatry, Lombroso supposedly is responsible for coining the term criminology. Lombroso was inspired by the work of Franz Joseph Gall and his phrenological theories, as well as Charles Darwin and Francis Galton’s work in criminology.

Lombroso was the first to build and experiment with a device measuring suspects’ pulse and blood pressure to determine signs of deception under police questioning. He called his invention the “Hydrosphygmograph.”

Dr. Lombroso published “L’Homme Criminel” (“The Criminal Man”) in 1985, showing documented cases of the use of his device, comprising a sphygmomanometer and plethysmograph during criminal interrogations.

 

William Marston – Providing Inspiration

Dr. William Moulton Marston was the first American to develop a lie detector instrument successfully in 1915. Marston called his device the “Systolic Blood Pressure Test.” He got the idea for creating the tool from his wife, who complained one day that she felt her blood pressure rise every time she got mad or excited.

Marston used this observation as the inspiration to create his lie detector. He infamously used the device in a case involving a murder, where he discovered the suspect falsely confessed to the crime. However, the courts disagreed with Marston’s work, discounting it inaccurately.

This case led to the forming of the Supreme Court denying the use of polygraph test results as admissible evidence in court. This legislation still holds up today, and despite the advances in polygraph technology, lie detector results are still not admissible as evidence in trials in many states across the US.

 

John Larson – The Breakthrough

Marston failed at getting his lie detector recognized as a valid instrument in deception detection in law enforcement cases. However, he did serve as the inspiration for the “Father of the Polygraph,” John A. Larson.

Larson was a medical student at UCLA and moonlighted with the Berkeley Police Department in California during his studies, becoming a full-time officer with the department after graduation. During his early days with the department, the Chief of Police, Augustus Vollmer, introduced him to Marston’s work on the Systolic Blood Pressure Test.

Larson developed his own polygraph device, “The Sphgggy,” by the media. It utilized the method of continuously registering changes in the examinee’s pulse rate, respiration, and blood pressure, under questioning.

Larson tested his device for the first time in 1923 on an individual suspected of shoplifting. The store owner knew the suspect lived in a local college dormitory but didn’t know their identity. Larson tested 38 individuals from the dorm, with 37 passing and one failing. This individual later confessed to the crime.

 

Leonard Keeler – Innovation and Refinement

While Larson formed the foundation for introducing the polygraph into law enforcement, his colleague, Leonard Keeler, brought it into infamy. Keeler worked alongside Larson at the Berkeley Police Department, drawing a keen interest in Larson’s work on his polygraph machine.

Keeler took up the mantle of developing the Sphyggy, redeveloping many of the inefficiencies in the device. For instance, he did away with the need for smoke paper, replacing it with chart paper and pens, allowing for a much easier setup by the examiner.

Keeler launched his version of the Larson polygraph, the “Emotograph,” in 1925. However, it was destroyed in a fire at his apartment the same year. Keeler turned to the Chicago-based firm, “Associated Research,” to assist him in rebuilding the machine.

Keeler patented his device in 1931 and continued developing the instrument. In 1936, he added the “Psychogalvanometer” to it, allowing him to monitor changes in the skin’s electrical resistance.

For the next three decades, Keeler’s device became the benchmark polygraph standard, helping police departments across the US solve thousands of cases. It also earned Keeler the title “The Father of the Modern Polygraph.”

Keeler joined the “Scientific Crime Detection Laboratory at Northwestern University” in Chicago in 1930. He rose through the ranks to the top of the organization to become its director between 1936 and 1938. By the mid-1930s, Keeler had conducted over 2,000 polygraphs on suspects, with exceptional success rates at determining deception during exams. He founded the “Keeler Polygraph Institute,” in 1948, located on Ohio Street in Chicago, becoming the world’s first polygraph school.

Keeler was also responsible for introducing polygraphy into national security agencies. In 1945, Keeler used his polygraph device to test German prisoners at Fort Getty, Rhode Island, volunteering for police duty in Germany.

The test results weeded out a third of the candidates with possible ties to the Nazis or unsuitable for the job for other reasons. As a result of the polygraph’s success, it was adopted by the CIA in the 1950s and used to screen agents in the Korean War in the 1950s and during the Cuban crisis in the 1960s.

The CIA formed the Central Intelligence Agency (CIA) Polygraph Division in 1948, instituting a policy requiring the mandatory screening of its employees and operatives every five years. National security agencies still use polygraphs in employee, candidate, and operative screening today.

 

Cleve Backster – Standardizing Analysis

Cleve Backster was a polygraph interrogator for the CIA after heading up Keelers Institute in the final years before Keeler’s death. As one of America’s leading polygraph specialists and former head of the Keeler Institute, Backster founded “the Cleve Backster School of Lie Detection” in Manhattan, New York.

Backster also made a huge contribution to the field of polygraphy and deception detection during his career. In 1960, he developed the “Backster Zone Comparison Technique.” Backster also developed a system of qualifying chart analysis, standardizing the procedure to make it more scientific and objective.

 

John E. Reid – Advancing Polygraph Questioning

While Larson and Keeler get the credit for developing and refining the polygraph device, John E. Reid is responsible for developing the questioning technique used in the test. Reid was a police officer and trained psychologist with a keen interest in polygraph science.

In 1945, Reid developed his instrument, “The Reid Polygraph.” In 1947, he created “The Reid Technique” for use in police interrogations of suspects. The Reid Technique is a nine-step process used during the lie detector test, with a huge success rate in getting confessions from criminals.

The Reid Polygraph would also become the benchmark standard for polygraph devices, replacing the Keeler polygraph as the gold standard in the industry. Reid added the features of recording muscular activity in the feet, forearms, and thighs, using metal bellows placed under the seat and arms of the chair. It was the first polygraph instrument to incorporate motion detection into the mix.

However, “The Reid Technique” was his big breakthrough, introducing the concept of control questions in the relevant/irrelevant questioning technique. This innovation earned Reid the title of “The Father of Controls.”

His questioning technique was so successful that national security agencies, such as the NSA, CIA, and FBI, adopted the Reid technique into their polygraph processes, initially using the Reid School to train their examiners.

The Reid Technique also underwent much controversy during its use. Many examinees claimed the technique coerced them into making a confession. However, it’s still in use today, with a leaked document showing the FBI still used The Reid Technique in their polygraph questioning practices in 2013.

 

The United States Vs. Frye & Admissibility of Polygraph Results in Court

Since its inception, there’s been controversy surrounding the accuracy of the lie detector and its validity in providing admissible evidence in court. The case bringing the question of polygraph accuracy into question is Frye vs. United States.

The case stems from Dr. William Marston’s use of his “Systolic Blood Pressure Test” on James Frye. Marston used his lie detector device to prove that Frye was coerced into falsely providing a confession to the murder of Dr. Brown.

However, Marston’s test supposedly proved that Frye was innocent. However, in the trial, Justice McCoy refused to accept the polygraph results as evidence that Frye was innocent. The District of Columbia Court of Appeals ruled on the James Frye appeal in 1923, rejecting the scientific validity of the polygraph because the new technology didn’t have significant general acceptance.

In 1975, over 50 years after the Frye verdict, Congress created the US Federal Rules of Evidence (FRE), providing guidance to federal judges involved in evidentiary matters. Rule 702 was enacted to address the admissibility of expert testimony based on technical, scientific, or specialized knowledge.

After many decades of debate, a 1993 US Supreme Court decision in the case of Daubert vs. Merrell Dow Pharmaceuticals decided FRE superseded the general-acceptance standards of Frye, outlining a list of factors for consideration by federal judges in evidentiary matters.

Despite the success of the Daubert decision, several state jurisdictions retain the original Frye standard in determining the admissibility of scientific polygraph evidence.

 

AVATAR – The Future of Law Enforcement Polygraphs

So, where is polygraph going in the future of law enforcement? The US, EU, and Canada collaborated on the world’s first AI-based polygraph system in 2016. The EU named its system “iBorderCtrl,” using it as part of a six-month pilot test into the system’s efficacy at spotting immigrants presenting a threat to the national security of Hungary or attempting to pass through customs with contraband.

The Hungarian National Police implemented iBorderCtrl at four border crossing points. The AI system asks incoming travelers questions such as, “what do you have in your suitcase?” The traveler answers the question, and the system follows up with, “If you open your suitcase and show me the contents, will it confirm your answers are true?”

So, how does it work? The answer – Body language and micro-expressions. The iBorderCtrl AI relies on 38 different micro-gestures produced in the traveler’s face when answering questions to determine deception. What’s amazing is that iBorderCtrl can adjust its facial expression analysis to suit the traveler’s language, gender, and ethnicity.

If the traveler passes the iBorderCtrl Test, they receive a QR code that allows them to pass through customs. However, if the traveler fails the screening, they must proceed to a human-based screening. According to the test control results, the team tested the tech on 30 subjects. Hal was told to lie, while the other half told the truth.

The results were astounding, with iBorderCtrl receiving a 76% accuracy rate. The iBorderCtrl team, based at Manchester Metropolitan University, UK, states they can increase the system’s accuracy by up to 85%. However, considering millions of people pass through EU borders every year, that will result in a large percentage of false positives, leading to a strain on Customs resources.

The United States ran a similar test on its AI-based system for immigrants crossing the southern border. The US named its project “AVATAR” (Automated Virtual Agent for Truth Assessments in Real-Time). The system produced similar results during its 2016 testing period, with US Customs and Border Patrol running the operation.

While these AI systems don’t have complete accuracy and are still below the threshold of what’s capable with polygraph exams, we can help but wonder what the future has in store for the polygraph industry as AI technology progresses.

Will systems like AVATAR and iBorderCtrl become useful in bolstering national security? OR will they turn travel into a dystopian future? Time will tell.