With global geopolitical tensions ever growing between all nations around the globe, a focus on stopping terrorist activities before they can carry out their nefarious plots is more important than ever. The events of 9/11 brought about a new “war on terror” that’s still ongoing today.

The events of September 2001 showed the United States intelligence and national security complex that there were many holes in its security infrastructure, leading to a tightening of policies. The war on terror continues, with malicious actors in high-risk countries planning to carry out terror plots in the United States and countries worldwide.

The polygraph exam plays a central role in US counterintelligence practices, helping agencies uncover terrorists and terrorist plots before they have a chance to reach fruition. By proactively doing something to stop terrorists before they can carry out their plans, US national security agencies make the country and the world a safer place.

So, can a lie detector uncover a terrorist or terrorist plan? Is it a valuable tool in the intelligence and national security community? OR does it have no effect on these issues? Let’s look into it in detail and see what we can find.


The History of Polygraphy in Law Enforcement

The polygraph was introduced into law enforcement practices in 1915, with Dr. William Marston, a Ph.D. in psychology, creating his device known as the “systolic blood pressure test.” His invention detected elevations in blood pressure in interviews when they lied.

It proved a valuable tool for law enforcement, but the world was seemingly unprepared for the technology at the time. In 1921, Marston used his device in the infamous case of United States Vs. Frye, where Marston used his instrument to prove James Frye gave a false confession of guilt toward a murder.

However, The District of Columbia court released a ruling stating that Marston’s device was inaccurate and there was little hard science to prove its efficacy in detecting the truth. Marston’s work laid the foundation for another Ph.D., John A. Larson, to create his own version of a lie detector while moonlighting with the Berkeley police department.

Larson’s ties to the law enforcement community saw his device used in dozens of cases involving crimes investigated by the Berkeley PD. During his work at the department, Larson teamed up with Leonard Keeler, who was fascinated by Larson’s device. Keeler went on to redesign it, producing his device, the “Emotograph.”

The Emotograph was a breakthrough device, doing away with many inefficiencies of Larson’s instrument, such as the smoke paper used to record the test data, replacing it with chart paper and pens. During the 1920s and 1930s, Keeler’s polygraph instrument was used in hundreds of criminal cases, taking many criminals off the street.


The Development of the Keeler Polygraph

The Keeler polygraph fast became the benchmark standard for lie detector devices. After a fire at his apartment destroyed the original Emotograph, Keeler sought assistance from “Associated Research,” a Chicago-based firm, in rebuilding the instrument.

His partnership with Associated Research lasted until he died in 1949. Associated Research carried Keeler’s mantle in the wake of his death, producing a series of polygraph models to be used in law enforcement operations.

Similarly, other companies, like Stoelting and Lafayette Instruments, jumped on the bandwagon, producing versions of the polygraph to be used in the private and public sectors. The Keeler polygraph was the industry gold standard, and it wasn’t long before the OSS/CIA started implementing its use in operations.


Keeler Model #6317 and the CIA

The most infamous version of the Keeler polygraph concerning national security has to be Model #6317. With the signing of the National Security Act in 1951, and the birth of the CIA, the agency implemented a polygraph policy for its operative and for suspected enemies of the United States in the Korean War during the 1950s.

Model #6317 saw huge success, uncovering Chinese spies and double agents in South Korean operations against the North Koreans during the war. The CIA used the device in its operations against the Cubans in the 1960s, peaking at the height of “The Cuban Missile Crisis.”

The Keeler Model #6317 remained in service throughout the 1970s before coming into competition with devices offered by other companies.


The Advancement of Software Polygraph Solutions

While the Keeler range of polygraphs was touted as highly effective instruments by the National Security complex, introducing software-based systems in the 1990s changed the

industry forever. Previously, the polygraph policies implemented by the CIA were touted by some as inaccurate. Some experts suggested the polygraph was only 50% to 70% effective at uncovering deception in an examinee.

However, the rapid development of software systems refined and enhanced polygraph accuracy. Today, the American Polygraph Association (APA) states polygraph software to be up to 87% accurate, while software producers claim the device is up to 97% accurate at detecting deception.

Regardless of the discrepancy in claims, it’s clear that the introduction of software-based polygraph systems remarkably increased polygraph accuracy and efficacy.


Can a Lie Detector Uncover a Terrorist or Terrorist Plan?

Organizations involved in National Security, such as the FBI, CIA, NSA, and DOD, still use polygraphs in their practices to question their employees, operatives, and detainees.

When combined with advanced interrogation techniques, the polygraph exam helped these organizations weed out potential threats to national security involving internal espionage and terrorist activities.

While the national security agency couldn’t manage to stop terrorist plots like 9/11, the polygraph played a significant role in helping agents uncover terrorists and their plans. So, how does the lie detector detect deception in examinees?


How the Polygraph Works

Like all other models before it, the modern polygraph device relies on detecting the activation of the “fight-or-flight” (FoF) response in the examinee. During an interrogation of a suspected terrorist, the polygraph examiner hooks the examinee into the system using instrumentation to monitor physiological changes in the examinee’s blood pressure, heart rate, respiration, sweat production, and skin electrical activity.

The polygraph software analysis feedback from this instrumentation, presenting it to the examiner in real-time on their laptop screen. The FoF activates when the examinee comes under the intense stress of having to lie during the interrogation. As the FoF comes into play, their vital signs elevate, showing the examiner the examinee might be acting deceptively.


The Difference Between Private Sector and Public Sector Polygraph Rules

Understanding the significant difference in polygraph exams executed in the private and public sectors is important. Ronald Reagan signed the “Employee Polygraph Protection Act of 1988” (EPPA) into power during the final days of his administration.

The EPPA gave employees and job candidates protection from employers in polygraph exams. However, these rules don’t apply to public sector organizations like those involved in national security. As a result, these agencies can use the polygraph as they see fit, both in employee hiring and firing practices and in interrogating individuals they think might be involved in terrorist activities.

The primary difference in the execution of polygraph exams in the national security industry and those in the private sector comes from the questions asked during the exam and the methodology used by the examiners.


The Role of the Examiner & The Reid Technique

While Associated Research of Chicago continually redeveloped the Keeler polygraph into a more effective device, the biggest change in polygraph science came from John E. Reid in the 1950s.

Reid was a trained psychologist and police officer. He used his knowledge to develop a new interrogation system initially used in law enforcement polygraph exams and then adopted by the intelligence and national security complex.

“The Reid Technique” involved a nine-step interrogation process executed by the examiner during the lie detector test. The goal of the Reid Technique was more to get the suspect to confess to a crime by the end of the progression rather than to detect deception in the examinee during the test.

The Reid Technique was highly effective at drawing confessions from examines, with the national security complex sending its examinees to the Reid Institute for training. However, the lack of training capacity in the Reid School led the DOD and the CIA to create independent examiner training courses based on the curriculum of the Reid Technique in the 1980s.

The examiners trained by these institutes were more along the lines of master interrogators than standard polygraph examiners. The escalation in their interrogation techniques sparked outrage among the employees involved in the national security complex, with many employees claiming the polygraph exam was responsible for creating “false positives” during the test due to the pressure applied to them by the examiner.


Are National Security Polygraphs Accurate?

The outcry from the intelligence community towards polygraph science was fierce, but agencies in national security continued to use the technology in employee screening practices and operations. The claims of inaccuracy, such as one agent being able to dupe a polygraph exam on two separate occasions, mainly came from the era of the Keeler polygraph.

The introduction of software systems and their enhanced accuracy in the industry supposedly reduced the number of false positives created in lie detector tests. To date, the FBI, CIA, and NSA claim the polygraph is useful in uncovering suspected terrorists and terrorist plots.


Can Terrorists Beat the Polygraph?

Despite the claims from agencies of the polygraph being accurate, some individuals, including ex-national security agents, claimed they could beat the polygraph exam using “countermeasures.” A countermeasure is a tactic the examinee deploys during the lie detector test.

For instance, the examinee could think of a bad thought when asked a question or implement a physical action, such as curling the toes, biting the cheek, or clenching the thigh muscle when responding to the examiner’s question.

These countermeasures supposedly interfered with the sympathetic nervous system’s ability to launch the FoF, resulting in an inconclusive result. However, it’s important to note that, once again, these countermeasures came from a time before the introduction of software-based polygraph systems.

The higher degree of accuracy brought to the table by software and computerized polygraph tools allowed the examiner to identify if the examinee was implementing countermeasures during the test, resulting in an immediate exam failure.

Today, countermeasures still exist, but examinees typically utilize drug-based tactics, such as using anti-anxiety drugs during the test. These drugs interfere with the body’s ability to launch the FoF. However, a trained examiner can still spot the changes in physiological response in the examinee, even if they use these drugs. As a result, the countermeasure is mostly ineffective.

Since terrorists are usually captured during covert operations and subjected to a lie detector test, they don’t have access to these drugs. However, double agents and infiltrators to national security organizations may decide to use them during the test in an attempt to help them go undetected.


In Closing – AI & the Future of Polygraph Science

Ports of entry into the United States present a serious threat to national security. Every day, thousands of people from Latin  American countries enter through the southern border. Too many people enter through these channels for the US Border Patrol and Customs authorities to assess.

So, to assist these agencies with their immigration assessments, the government is turning to Artificial Intelligence for assistance. The US, EU, and Canada collaborated on an AI-based polygraph system to be used at border crossings.

The system, Known as “AVATAR” (Automated Virtual Agent for Truth Assessments in Real-Time), is an automated program designed to ask immigrants questions, scanning their faces for micro-expressions and changes in vocal tones when they answer.

According to the testing done on the system, it presents an accuracy rating of up to 85%. If the AVATAR system detects possible deception in the interviewee, it refers them to a Customs or Border Patrol agent for a more in-depth interview.

An AI-based system like AVATAR helps to conserve resources at these agencies while identifying more potential terrorist threats during the screening process, enhancing national security.

So, we can consider that the future of polygraphy is moving in this direction, and with AI technology becoming more accurate and advanced by the day, it might present a new frontier in detecting possible terrorists or terrorist plots in the future.