Stoelting Company: 140 Years of Polygraph Innovation

Christian Hans Stoelting and the Chicago Origins

The story of the Stoelting Company begins in 1886, when Christian Hans Stoelting — a German immigrant born in 1865 — established the Chicago Laboratory Supply and Scale Company on Chicago's west side [1]Verified Stoelting - Smithsonian National Museum of American History Collection
Confirms Christian Hans Stoelting (1865-1943) was a German immigrant who founded Chicago Laboratory Supply and Scale Co. in 1886, renamed C.H. Stoelting Co. by 1903, received 1918 U.S. Navy contract, and holds trade catalogs in Smithsonian collection. From these humble beginnings, Stoelting built his enterprise into one of the most respected scientific instrument firms in America [2]Verified Stoelting Co. - About Us
Confirms company history from Chicago Laboratory Supply and Scale Co. founding in 1886, dominance of American psychology apparatus market 1903-1943, St. Louis Exposition medals, and current Wood Dale, Illinois headquarters.

By 1903, the firm had become the C.H. Stoelting Co., specializing in apparatus for psychological testing [1]Verified Stoelting - Smithsonian National Museum of American History Collection
Confirms Christian Hans Stoelting (1865-1943) was a German immigrant who founded Chicago Laboratory Supply and Scale Co. in 1886, renamed C.H. Stoelting Co. by 1903, received 1918 U.S. Navy contract, and holds trade catalogs in Smithsonian collection. From 1903 to 1943, Stoelting was nearly unchallenged as the principal provider of the material culture of American psychology [2]Verified Stoelting Co. - About Us
Confirms company history from Chicago Laboratory Supply and Scale Co. founding in 1886, dominance of American psychology apparatus market 1903-1943, St. Louis Exposition medals, and current Wood Dale, Illinois headquarters. The company's early focus on physiology quickly expanded to embrace the broader world of scientific psychology, and as early as 1895, Stoelting was supplying apparatus specifically tailored for psychological research [3]Verified Christian Hans Stoelting - Biographical Information
Confirms Stoelting Company was established in 1886, supplied apparatus for psychology as early as 1895, and won medals at the 1904 St. Louis Exposition.

Christian Hans Stoelting's vision positioned his company at the intersection of science and industry during a period of extraordinary growth in American experimental psychology. The company's location in Chicago placed it at the heart of a vibrant academic and scientific community that would prove instrumental in the development of lie detection technology.

Early Recognition and the St. Louis Exposition

Stoelting's reputation for quality was recognized early. At the St. Louis Universal Exposition of 1904, C.H. Stoelting Co. was awarded Medals for Anthropometric Apparatus and Psychometric Apparatus — awards that remain displayed at the company's headquarters to this day [2]Verified Stoelting Co. - About Us
Confirms company history from Chicago Laboratory Supply and Scale Co. founding in 1886, dominance of American psychology apparatus market 1903-1943, St. Louis Exposition medals, and current Wood Dale, Illinois headquarters.

The company's psychological tests became widely used in institutional settings. Stoelting tests were among the types of non-verbal tests routinely administered to immigrants at Ellis Island in the early 20th century [4]Verified Stoelting Tests at Ellis Island - Google Arts & Culture
Confirms Stoelting tests were administered to immigrants at Ellis Island in the early 20th century and failure was cause to deny entrance. The company's instruments for measuring cognitive ability, sensory perception, and physiological response established the foundation for its later entry into polygraph manufacturing.

In June 1918, during World War I, the company received a contract to produce quadrants for the U.S. Navy [1]Verified Stoelting - Smithsonian National Museum of American History Collection
Confirms Christian Hans Stoelting (1865-1943) was a German immigrant who founded Chicago Laboratory Supply and Scale Co. in 1886, renamed C.H. Stoelting Co. by 1903, received 1918 U.S. Navy contract, and holds trade catalogs in Smithsonian collection, demonstrating its capacity for precision instrument manufacturing in service of the federal government — a relationship that would deepen considerably with the advent of polygraph technology.

Dominance of the Psychology Apparatus Market

Between 1903 and 1943, Stoelting's dominance of the American psychology apparatus market was virtually complete [2]Verified Stoelting Co. - About Us
Confirms company history from Chicago Laboratory Supply and Scale Co. founding in 1886, dominance of American psychology apparatus market 1903-1943, St. Louis Exposition medals, and current Wood Dale, Illinois headquarters. The company manufactured an extensive range of instruments spanning psychology, psychometry, psychotechnology, psychiatry, neurology, anthropology, phonetics, physiology, and pharmacology [3]Verified Christian Hans Stoelting - Biographical Information
Confirms Stoelting Company was established in 1886, supplied apparatus for psychology as early as 1895, and won medals at the 1904 St. Louis Exposition. This breadth of scientific manufacturing capability gave Stoelting a unique advantage when the emerging field of polygraph technology demanded sophisticated physiological recording instruments.

The Smithsonian National Museum of American History holds trade catalogs from C.H. Stoelting Co. documenting the company's extensive product lines, including polygraphs and recorders, vision and tactile instruments, anthropometric and psychometric apparatus, timing devices, and lie detecting sets [1]Verified Stoelting - Smithsonian National Museum of American History Collection
Confirms Christian Hans Stoelting (1865-1943) was a German immigrant who founded Chicago Laboratory Supply and Scale Co. in 1886, renamed C.H. Stoelting Co. by 1903, received 1918 U.S. Navy contract, and holds trade catalogs in Smithsonian collection. These archival materials testify to the depth and range of Stoelting's contribution to American science.

For researchers interested in the broader evolution of deception detection science, our guide on how a polygraph works explains the physiological principles that Stoelting's instruments were designed to measure.

Chicago: The Capital of Polygraph Development

Stoelting's Chicago location placed the company at the epicenter of polygraph innovation. Chicago and the Midwest were considered the center of the polygraph world during a significant portion of the 20th century [5]Verified Biography of Leonarde Keeler - American Polygraph Association
Confirms Chicago and the Midwest were considered the center of the polygraph world during a significant portion of the 20th century. The city was home to two of the early, leading practitioners — John E. Reid and Leonarde Keeler — both affiliated with Northwestern University's Scientific Crime Detection Laboratory (SCDL) [6]Verified Chicago: Birthplace of Modern Polygraphy
Confirms Reid had instruments specially manufactured by Stoelting, Reid and Keeler were both affiliated with Northwestern's SCDL, and documents the centrality of Chicago to polygraph development.

The SCDL, established in 1929 as America's first independent forensic crime laboratory, undertook a wide range of scientific case work during the 1930s, including polygraph testing [7]Verified Teaching Forensic Science: The Scientific Crime Detection Laboratory, 1929-1938
Confirms Northwestern University's SCDL was established in 1929 as America's first independent forensic crime laboratory, conducted polygraph testing among other scientific casework. Leonarde Keeler led its psychology department, bringing the lie detector to prominence [8]Verified Scientific Crime Detection Laboratory - Chicagology
Confirms the SCDL was established in Fall 1929 at Northwestern, Leonarde Keeler headed the psychology department, and the Wickersham Commission praised the laboratory. This concentration of polygraph expertise in Chicago created a ready market for Stoelting's precision instruments and laid the groundwork for the company's entry into polygraph manufacturing.

Fred Inbau, who managed the SCDL after Calvin Goddard's departure, became another crucial Chicago figure in polygraph history [8]Verified Scientific Crime Detection Laboratory - Chicagology
Confirms the SCDL was established in Fall 1929 at Northwestern, Leonarde Keeler headed the psychology department, and the Wickersham Commission praised the laboratory. Learn more about his contributions in our profile of Fred Inbau and the polygraph. The Wickersham Commission specifically praised the SCDL in 1931 as having no equal in the country [8]Verified Scientific Crime Detection Laboratory - Chicagology
Confirms the SCDL was established in Fall 1929 at Northwestern, Leonarde Keeler headed the psychology department, and the Wickersham Commission praised the laboratory.

The First Cardio-Pneumo Polygraph

Stoelting created its first Cardio-Pneumo Polygraph in 1935 [9]Verified Stoelting Polygraph Division - Our Company History
Confirms first Cardio-Pneumo Polygraph in 1935, Reid polygraph in 1951, Deceptograph standardized by military in 1958, Polyscribe 1974, Ultrascribe 1978, Executive Ultrascribe 1982, CAPS 1988, CPS 1992, entering a market that was rapidly developing alongside the professionalization of law enforcement. This first instrument recorded two channels — pneumo and cardio tracings — on six-inch paper using a two-pen inking system [10]Verified Stoelting Polygraph Instrument Technical Documentation
Confirms Deceptograph Model 22500 specifications, Cleve Backster's design role in early Cardio-Pneumo, Model 22600 details, and technical specifications of all three instruments. It operated on standard 115-volt current without alternate battery capacity and was considered very sensitive for its time [10]Verified Stoelting Polygraph Instrument Technical Documentation
Confirms Deceptograph Model 22500 specifications, Cleve Backster's design role in early Cardio-Pneumo, Model 22600 details, and technical specifications of all three instruments.

The instrument was originally designed by Cleve Backster, who presented his plans to the Stoelting Company, which made some minor design variations before it went into production in the early 1950s [10]Verified Stoelting Polygraph Instrument Technical Documentation
Confirms Deceptograph Model 22500 specifications, Cleve Backster's design role in early Cardio-Pneumo, Model 22600 details, and technical specifications of all three instruments. While the initial 1935 model was simpler, it marked Stoelting's entry into a field that would become central to the company's identity.

Notably, this was the same era when Leonarde Keeler's polygraph instruments were being manufactured by Associated Research, Inc., a Chicago firm established in 1936 by James F. Inman (1902–1959) [11]Verified Polygraph - National Museum of American History (Associated Research)
Confirms Associated Research, Inc. was the manufacturer of Keeler polygraphs, established in Chicago in 1936 by James F. Inman (1902-1959). Both Stoelting and Associated Research operated in Chicago, and alongside Lafayette Instrument Company, they formed the core of American polygraph instrument manufacturing [12]Verified A History of Polygraph Digitization
Confirms Lafayette and Stoelting were the two primary analog polygraph manufacturers who deployed computer systems.

The Photopolygraph and Early Innovations

Even before the 1935 Cardio-Pneumo Polygraph, Stoelting had produced instruments relevant to deception detection research. The Photopolygraph, developed by Chester W. Darrow in 1930, was produced by Stoelting and cost $999 [13]Verified Europolygraph Academy - History of Polygraph Instruments
Confirms Photopolygraph (1930) developed by Darrow and produced by Stoelting for $999; Deceptograph 22500 (1955) as most widely used polygraph; Polyscribe (1974) as first fully electronic polygraph. The Darrow Behavior Research Photopolygraph was developed and intended solely for behavior research experiments [14]Verified Polygraph - Wikipedia (Darrow Photopolygraph)
Confirms the Darrow Behavior Research Photopolygraph was developed and intended solely for behavior research experiments, but its production demonstrated Stoelting's capacity to build sophisticated physiological recording equipment.

In 1946, Stoelting introduced electronic recording channels to its polygraph instruments — another industry first [15]Verified Stoelting Polygraph Instruments - The Polygraph Museum
Confirms Stoelting produced first modern polygraph in 1935, electronic recording channels in 1946, multifunction channels 1966, CAM 1968, modular design 1977, CLC re-centering 1980, CAPS 1988, CPS 1992. This advancement replaced purely mechanical recording mechanisms with electronic components that offered greater sensitivity and reliability in capturing physiological data. These incremental innovations during the 1930s and 1940s positioned Stoelting as the leading manufacturer of polygraph instruments heading into the post-war era.

John E. Reid and the Reid Polygraph (1951)

Many prominent polygraph examiners and schools chose to have their own line of polygraphs manufactured by Stoelting [9]Verified Stoelting Polygraph Division - Our Company History
Confirms first Cardio-Pneumo Polygraph in 1935, Reid polygraph in 1951, Deceptograph standardized by military in 1958, Polyscribe 1974, Ultrascribe 1978, Executive Ultrascribe 1982, CAPS 1988, CPS 1992. The most significant of these collaborations was with John E. Reid, a lawyer from Chicago who developed the Control Question Technique (CQT) between 1945 and 1947 [16]Verified History of Polygraph - Ohio Polygraph Services
Confirms Reid developed CQT in 1947, Backster developed Zone Comparison Technique in 1960, and Kircher & Raskin developed CAPS in 1988. Reid's work at detecting self-induced blood pressure responses led him to develop a device to detect countermeasure efforts, which he had specially manufactured by the Stoelting Company [6]Verified Chicago: Birthplace of Modern Polygraphy
Confirms Reid had instruments specially manufactured by Stoelting, Reid and Keeler were both affiliated with Northwestern's SCDL, and documents the centrality of Chicago to polygraph development.

In 1951, the Reid Polygraph was introduced [9]Verified Stoelting Polygraph Division - Our Company History
Confirms first Cardio-Pneumo Polygraph in 1935, Reid polygraph in 1951, Deceptograph standardized by military in 1958, Polyscribe 1974, Ultrascribe 1978, Executive Ultrascribe 1982, CAPS 1988, CPS 1992. This was a groundbreaking five-channel model capable of recording signals from arm movements, respiration, GSR, blood pressure, and thigh movements [9]Verified Stoelting Polygraph Division - Our Company History
Confirms first Cardio-Pneumo Polygraph in 1935, Reid polygraph in 1951, Deceptograph standardized by military in 1958, Polyscribe 1974, Ultrascribe 1978, Executive Ultrascribe 1982, CAPS 1988, CPS 1992. The inclusion of movement detection channels reflected Reid's pioneering research into countermeasure detection, making the Reid Polygraph one of the most advanced instruments of its era.

Reid's contributions extended far beyond instrumentation. He developed the Control Question Technique, which replaced the earlier Relevant/Irrelevant Question Technique and became the most significant methodological innovation in polygraph history [16]Verified History of Polygraph - Ohio Polygraph Services
Confirms Reid developed CQT in 1947, Backster developed Zone Comparison Technique in 1960, and Kircher & Raskin developed CAPS in 1988. His foundational text, co-authored with Fred Inbau, "Lie Detection and Criminal Interrogation," became the standard reference in the field [17]Verified Lie Detection and Criminal Interrogation. By Fred E. Inbau and John E. Reid
Review of Inbau and Reid's foundational text on lie detection and criminal interrogation methods.

Cleve Backster and the Zone Comparison Technique

Cleve Backster (February 27, 1924 – June 24, 2013) was a CIA interrogation specialist who became one of the most influential figures in polygraph methodology [18]Verified Cleve Backster - Wikipedia
Confirms Cleve Backster (1924-2013) was CIA interrogation specialist who founded Backster School of Lie Detection in New York City in 1960, later in San Diego, and used Stoelting 22500. Building upon the Reid Control Question Technique, Backster developed the Zone Comparison Technique (ZCT) in 1960, which primarily involved an alteration of the Reid question sequencing [19]Verified History of Polygraph - Backster Zone Comparison
Confirms Cleve Backster developed Zone Comparison Technique in 1960, introduced quantification system for chart analysis adopted as standard procedure. He also introduced a quantification system of chart analysis that made polygraph scoring more objective and scientific [19]Verified History of Polygraph - Backster Zone Comparison
Confirms Cleve Backster developed Zone Comparison Technique in 1960, introduced quantification system for chart analysis adopted as standard procedure.

Backster's system for the numerical evaluation of physiological data collected from polygraph charts has been adopted as standard procedure in the polygraph field today [19]Verified History of Polygraph - Backster Zone Comparison
Confirms Cleve Backster developed Zone Comparison Technique in 1960, introduced quantification system for chart analysis adopted as standard procedure. He used the Stoelting 22500 in his research and practice [18]Verified Cleve Backster - Wikipedia
Confirms Cleve Backster (1924-2013) was CIA interrogation specialist who founded Backster School of Lie Detection in New York City in 1960, later in San Diego, and used Stoelting 22500, and the MythBusters television program later used the same model of polygraph in their experiments [18]Verified Cleve Backster - Wikipedia
Confirms Cleve Backster (1924-2013) was CIA interrogation specialist who founded Backster School of Lie Detection in New York City in 1960, later in San Diego, and used Stoelting 22500.

Backster founded the Backster School of Lie Detection in New York City in 1960 after leaving his position with the CIA, later relocating to San Diego, California [18]Verified Cleve Backster - Wikipedia
Confirms Cleve Backster (1924-2013) was CIA interrogation specialist who founded Backster School of Lie Detection in New York City in 1960, later in San Diego, and used Stoelting 22500. Learn more about his fascinating career in our guide to the Backster Zone Comparison Test and his remarkable plant experiments and polygraph legacy.

The Model 22500 (1955)

In about 1955, the Stoelting Company introduced the Deceptograph Model 22500, which would become the most widespread and most widely used polygraph instrument in the world [20]Verified Stoelting Deceptograph 22500 - Europolygraph Academy
Confirms Deceptograph 22500 (1955) was the most widespread and most widely used polygraph instrument in the world, implemented in U.S. military. The 22500 contained vacuum tubes in its amplifier, which required approximately thirty minutes of warm-up time before use [10]Verified Stoelting Polygraph Instrument Technical Documentation
Confirms Deceptograph Model 22500 specifications, Cleve Backster's design role in early Cardio-Pneumo, Model 22600 details, and technical specifications of all three instruments. It featured three recording channels — cardio, pneumo, and GSR — providing a continuous recording of changes in relative blood pressure, heart rate, pulse wave amplitude, respiration, and electrical skin resistance [10]Verified Stoelting Polygraph Instrument Technical Documentation
Confirms Deceptograph Model 22500 specifications, Cleve Backster's design role in early Cardio-Pneumo, Model 22600 details, and technical specifications of all three instruments.

The AC component unit was packaged in an aluminum Halliburton case with sectionalized components and a built-in microphone cartridge [10]Verified Stoelting Polygraph Instrument Technical Documentation
Confirms Deceptograph Model 22500 specifications, Cleve Backster's design role in early Cardio-Pneumo, Model 22600 details, and technical specifications of all three instruments. The 22500 weighed approximately thirty-one pounds with its accessories, with dimensions of 18" x 9" x 6" [10]Verified Stoelting Polygraph Instrument Technical Documentation
Confirms Deceptograph Model 22500 specifications, Cleve Backster's design role in early Cardio-Pneumo, Model 22600 details, and technical specifications of all three instruments. It used standard 110-volt, 60-cycle alternating current and featured an individual inking system with a pen tip, fork, counterbalance, plastic tubing, ink reservoir, and receptacle [10]Verified Stoelting Polygraph Instrument Technical Documentation
Confirms Deceptograph Model 22500 specifications, Cleve Backster's design role in early Cardio-Pneumo, Model 22600 details, and technical specifications of all three instruments.

A Stoelting Deceptograph is preserved in the permanent collection of the Smithsonian National Museum of American History, with an inscription reading "DECEPTOGRAPH / PATENT APPLIED FOR / C. H. STOELTING CO. / CHICAGO, 24 ILL." [21]Verified Deceptograph - Smithsonian National Museum of American History
Confirms Stoelting Deceptograph held in permanent Smithsonian collection with inscription from C. H. Stoelting Co., Chicago.

U.S. Military Standardization (1958)

In 1958, the Stoelting Deceptograph was standardized by the U.S. military [9]Verified Stoelting Polygraph Division - Our Company History
Confirms first Cardio-Pneumo Polygraph in 1935, Reid polygraph in 1951, Deceptograph standardized by military in 1958, Polyscribe 1974, Ultrascribe 1978, Executive Ultrascribe 1982, CAPS 1988, CPS 1992, cementing its position as the instrument of choice for government polygraph programs. This military adoption was a landmark moment — it meant that thousands of military polygraph examiners across the armed forces would be trained on and operate Stoelting instruments.

The U.S. Army polygraph screening program utilized multiple Stoelting models over the decades, including the Executive 22532, Executive Polyscribe 22776, and Ultrascribe 80545X [22]Verified Barland Validation Study - U.S. Army Polygraph Screening
Confirms U.S. Army polygraph examiners used multiple Stoelting models including Executive 22532, Executive Polyscribe 22776, and Ultrascribe 80545X. This long-standing relationship between Stoelting and the Department of Defense demonstrated the trust placed in Stoelting's precision engineering.

The 1958 standardization also had implications for polygraph training. Military polygraph schools trained their students on Stoelting equipment, which meant that examiners entering the private sector or civilian government service carried their familiarity with Stoelting instruments throughout their careers.

The Model 22600 Emotional Stress Monitor (1966)

The Model 22600 Polygraph instrument was introduced by Stoelting in 1966 [10]Verified Stoelting Polygraph Instrument Technical Documentation
Confirms Deceptograph Model 22500 specifications, Cleve Backster's design role in early Cardio-Pneumo, Model 22600 details, and technical specifications of all three instruments. This instrument replaced the 22500 model, with the most significant change being the replacement of old vacuum tubes with transistors, which reduced the weight and size of the instrument and eliminated the previous thirty-minute warm-up time [10]Verified Stoelting Polygraph Instrument Technical Documentation
Confirms Deceptograph Model 22500 specifications, Cleve Backster's design role in early Cardio-Pneumo, Model 22600 details, and technical specifications of all three instruments.

The 22600 was a three-pen instrument with a mechanical recording channel for respiration on the top channel, a 250,000-ohm GSR amplifier on the middle channel, and a bottom channel for recording heart rate and changes in relative blood pressure [10]Verified Stoelting Polygraph Instrument Technical Documentation
Confirms Deceptograph Model 22500 specifications, Cleve Backster's design role in early Cardio-Pneumo, Model 22600 details, and technical specifications of all three instruments. In 1966, Stoelting also created the first polygraph with a non-battery powered galvanometer [9]Verified Stoelting Polygraph Division - Our Company History
Confirms first Cardio-Pneumo Polygraph in 1935, Reid polygraph in 1951, Deceptograph standardized by military in 1958, Polyscribe 1974, Ultrascribe 1978, Executive Ultrascribe 1982, CAPS 1988, CPS 1992.

The 22600 was the last instrument produced by Stoelting that utilized the single pneumograph and six-inch chart paper [10]Verified Stoelting Polygraph Instrument Technical Documentation
Confirms Deceptograph Model 22500 specifications, Cleve Backster's design role in early Cardio-Pneumo, Model 22600 details, and technical specifications of all three instruments. A few years after the 22600 was introduced, Stoelting produced its first four-pen polygraph, which incorporated a second pneumograph and a kymograph recording on eight-inch paper [10]Verified Stoelting Polygraph Instrument Technical Documentation
Confirms Deceptograph Model 22500 specifications, Cleve Backster's design role in early Cardio-Pneumo, Model 22600 details, and technical specifications of all three instruments — another step toward the multi-channel instruments that would become the standard.

Federal and Military Partnerships

Stoelting's relationship with the U.S. government deepened significantly during the post-war period. The company's instruments became standard equipment for federal agencies conducting national security screening, counterintelligence investigations, and criminal examinations. The military's 1958 standardization of the Deceptograph was followed by decades of continued procurement of Stoelting models for the Army, Air Force, and Department of Defense Polygraph Institute [22]Verified Barland Validation Study - U.S. Army Polygraph Screening
Confirms U.S. Army polygraph examiners used multiple Stoelting models including Executive 22532, Executive Polyscribe 22776, and Ultrascribe 80545X.

This era also saw the expansion of polygraph use in law enforcement across the United States. As polygraph examining became increasingly professionalized throughout the 1950s and 1960s, demand for reliable instruments grew substantially. Stoelting, as one of only two primary manufacturers alongside Lafayette Instrument Company, was perfectly positioned to meet this demand [12]Verified A History of Polygraph Digitization
Confirms Lafayette and Stoelting were the two primary analog polygraph manufacturers who deployed computer systems.

For more on the broader context of polygraph use in law enforcement hiring, see our guide to the ALEA Polygraph for Alabama Law Enforcement hiring.

The Employee Polygraph Protection Act Era

The passage of the Employee Polygraph Protection Act (EPPA) in 1988 banned most private employer polygraph use while maintaining exceptions for government, security, and pharmaceutical industries [23]Verified Employee Polygraph Protection Act: 20 Years Later
Analyses of the 1988 EPPA's impact, banning most private employer polygraph use while maintaining exceptions for government and security. While this legislation reduced the commercial market for polygraph instruments in the private sector, it reinforced the importance of government and law enforcement polygraph programs — areas where Stoelting instruments were already deeply entrenched.

The EPPA's exemptions for government agencies, national security screening, and certain regulated industries meant that demand for high-quality polygraph instruments remained strong among Stoelting's core customers. The legislation also contributed to the professionalization of the field by concentrating polygraph use among trained, professional examiners working in official capacities.

The Stoelting Polyscribe: World's First Electronic Polygraph (1974)

In 1974, Stoelting released the world's first all-electronic polygraph — the Polyscribe [9]Verified Stoelting Polygraph Division - Our Company History
Confirms first Cardio-Pneumo Polygraph in 1935, Reid polygraph in 1951, Deceptograph standardized by military in 1958, Polyscribe 1974, Ultrascribe 1978, Executive Ultrascribe 1982, CAPS 1988, CPS 1992. This represented a revolutionary leap in polygraph technology, replacing mechanical recording mechanisms with solid-state electronics. The Polyscribe (Model 22770) featured four modules with dual functionality, capable of handling both pneumographic and electrical inputs [24]Verified Polyscribe Model 22770 - Worthpoint / The Henry Ford
Confirms the Polyscribe was the world's first all electronic polygraph instrument, with dual functionality modules and solid state GSR components, produced 1974-1979.

The Polyscribe incorporated solid-state GSR components that offered unprecedented sensitivity and stability in electrodermal recording [24]Verified Polyscribe Model 22770 - Worthpoint / The Henry Ford
Confirms the Polyscribe was the world's first all electronic polygraph instrument, with dual functionality modules and solid state GSR components, produced 1974-1979. It was produced until approximately 1977–1979 [24]Verified Polyscribe Model 22770 - Worthpoint / The Henry Ford
Confirms the Polyscribe was the world's first all electronic polygraph instrument, with dual functionality modules and solid state GSR components, produced 1974-1979 and is preserved in The Henry Ford Museum's permanent collection [25]Verified Polyscribe Model 22770 - The Henry Ford Museum Collection
Confirms the Stoelting Polyscribe (1974-1977) is held in The Henry Ford Museum permanent collection, alongside other landmark American innovations.

The significance of the Polyscribe cannot be overstated — it demonstrated that electronic recording technology could match and surpass the reliability of traditional mechanical ink-pen systems. This paved the way for all subsequent computerized polygraph systems and established Stoelting as the undisputed technology leader in the field.

The Ultrascribe Series (1978–1983)

In 1978, the Stoelting Ultrascribe was released [9]Verified Stoelting Polygraph Division - Our Company History
Confirms first Cardio-Pneumo Polygraph in 1935, Reid polygraph in 1951, Deceptograph standardized by military in 1958, Polyscribe 1974, Ultrascribe 1978, Executive Ultrascribe 1982, CAPS 1988, CPS 1992. This instrument introduced modular design to polygraph instruments, allowing examiners to select between three and five user-selected channels [9]Verified Stoelting Polygraph Division - Our Company History
Confirms first Cardio-Pneumo Polygraph in 1935, Reid polygraph in 1951, Deceptograph standardized by military in 1958, Polyscribe 1974, Ultrascribe 1978, Executive Ultrascribe 1982, CAPS 1988, CPS 1992. This flexibility gave examiners more freedom than ever before, as they could choose exactly how many channels they needed, and upgrades were inexpensive and straightforward [9]Verified Stoelting Polygraph Division - Our Company History
Confirms first Cardio-Pneumo Polygraph in 1935, Reid polygraph in 1951, Deceptograph standardized by military in 1958, Polyscribe 1974, Ultrascribe 1978, Executive Ultrascribe 1982, CAPS 1988, CPS 1992.

The modular design concept, first introduced by Stoelting in 1977 [15]Verified Stoelting Polygraph Instruments - The Polygraph Museum
Confirms Stoelting produced first modern polygraph in 1935, electronic recording channels in 1946, multifunction channels 1966, CAM 1968, modular design 1977, CLC re-centering 1980, CAPS 1988, CPS 1992, was another industry first that influenced all subsequent polygraph instrument design. Rather than purchasing an entirely new instrument when additional channels were needed, examiners could simply add modules to their existing Ultrascribe.

In 1982, the Executive Ultrascribe hit the market [9]Verified Stoelting Polygraph Division - Our Company History
Confirms first Cardio-Pneumo Polygraph in 1935, Reid polygraph in 1951, Deceptograph standardized by military in 1958, Polyscribe 1974, Ultrascribe 1978, Executive Ultrascribe 1982, CAPS 1988, CPS 1992. This smaller, lighter polygraph represented a significant improvement in form factor and became the official polygraph of the U.S. Army [9]Verified Stoelting Polygraph Division - Our Company History
Confirms first Cardio-Pneumo Polygraph in 1935, Reid polygraph in 1951, Deceptograph standardized by military in 1958, Polyscribe 1974, Ultrascribe 1978, Executive Ultrascribe 1982, CAPS 1988, CPS 1992. The final incarnation, the Ultrascribe II released in 1983, featured microprocessor-controlled re-centering [9]Verified Stoelting Polygraph Division - Our Company History
Confirms first Cardio-Pneumo Polygraph in 1935, Reid polygraph in 1951, Deceptograph standardized by military in 1958, Polyscribe 1974, Ultrascribe 1978, Executive Ultrascribe 1982, CAPS 1988, CPS 1992 — a technology that automatically maintained optimal tracing positions on the chart paper, reducing the need for manual adjustments during examinations.

Timeline of Stoelting's Analog-Era Innovations

Stoelting's record of polygraph firsts during the analog era is remarkable. Electronic recording channels were introduced by Stoelting in 1946. Multifunction recording channels followed in 1966. The CAM (Channel Activity Monitor) was introduced in 1968. Modular design arrived in 1977. CLC (Closed Loop Control) re-centering was introduced in 1980 [15]Verified Stoelting Polygraph Instruments - The Polygraph Museum
Confirms Stoelting produced first modern polygraph in 1935, electronic recording channels in 1946, multifunction channels 1966, CAM 1968, modular design 1977, CLC re-centering 1980, CAPS 1988, CPS 1992. Each of these innovations improved the examiner's ability to capture and interpret physiological data with greater precision.

This continuous stream of engineering advances ensured that Stoelting instruments remained the preferred choice of polygraph examiners throughout the analog era. The company's commitment to innovation reflected the broader evolution of the polygraph profession from intuitive-based practice toward evidence-based practice [26]Verified The Centennial Introspection Project: 100 Years of Polygraph Practice
Documents the polygraph profession's shift from intuitive-based to evidence-based practice over its first century, as documented in our research database. For a comprehensive look at how the profession transformed, see the insights from James Allan Matte's research on foremost changes in polygraph [27]Verified Foremost Changes in Polygraph in Last 100 Years
Identifies key transformations including evolution from basic lie detection to validated testing techniques with computerized scoring.

The Computer Aided Polygraph System — CAPS (1988)

The arrival of the Computer Aided Polygraph System (CAPS) in 1988 marked the beginning of the digital revolution in polygraph technology [9]Verified Stoelting Polygraph Division - Our Company History
Confirms first Cardio-Pneumo Polygraph in 1935, Reid polygraph in 1951, Deceptograph standardized by military in 1958, Polyscribe 1974, Ultrascribe 1978, Executive Ultrascribe 1982, CAPS 1988, CPS 1992. CAPS was developed by Drs. John C. Kircher and David C. Raskin at the University of Utah [28]Verified Computer Assisted Polygraph System (CAPS) - British Polygraph Society
Confirms CAPS was developed by David Raskin and John Kircher of University of Utah, interfaced analog polygraphs with computers, and was later replaced by CPS. It was the first system to interface field analog polygraphs with a computer, permitting modified field analog polygraphs to have their signals extracted from pen drive motors, digitized, stored, edited, and analyzed [28]Verified Computer Assisted Polygraph System (CAPS) - British Polygraph Society
Confirms CAPS was developed by David Raskin and John Kircher of University of Utah, interfaced analog polygraphs with computers, and was later replaced by CPS.

Critically, CAPS incorporated the first algorithm to be used for evaluating physiological data collected for diagnostic purposes [29]Verified Comprehensive History of the Polygraph - 90210 Polygraph
Confirms Kircher and Raskin developed CAPS in 1988, PolyScore completed at Johns Hopkins in 1993, and validated algorithms exceeded 98% accuracy. Discriminant analysis was used to weigh and combine measurements, and the software produced a statement of the probability of deception [28]Verified Computer Assisted Polygraph System (CAPS) - British Polygraph Society
Confirms CAPS was developed by David Raskin and John Kircher of University of Utah, interfaced analog polygraphs with computers, and was later replaced by CPS. This represented a fundamental shift from purely subjective human scoring to algorithm-assisted analysis — a transformation that would define the future of the profession.

The University of Utah research that produced CAPS drew on years of laboratory and field studies. Kircher and Raskin's work demonstrated that computer-based analysis could match or exceed the accuracy of experienced human examiners, establishing the scientific foundation for all subsequent computerized scoring systems [30]Verified Evaluating Polygraph Data - National Research Council / National Academies Press
Confirms Stoelting uses CPS developed by Scientific Assessment Technologies based on University of Utah research; notes Stoelting records skin conductance; documents CAPS and CPS development. To understand the full impact of this digital revolution, explore our guide on how software changed the lie detector test.

The Computerized Polygraph System — CPS (1992)

In 1992, the fully Computerized Polygraph System (CPS) replaced CAPS, marking the polygraph's official entrance into the computer age [9]Verified Stoelting Polygraph Division - Our Company History
Confirms first Cardio-Pneumo Polygraph in 1935, Reid polygraph in 1951, Deceptograph standardized by military in 1958, Polyscribe 1974, Ultrascribe 1978, Executive Ultrascribe 1982, CAPS 1988, CPS 1992. CPS was developed by Scientific Assessment Technologies, based on the University of Utah research conducted by Kircher and Raskin [30]Verified Evaluating Polygraph Data - National Research Council / National Academies Press
Confirms Stoelting uses CPS developed by Scientific Assessment Technologies based on University of Utah research; notes Stoelting records skin conductance; documents CAPS and CPS development. Unlike CAPS, which retrofitted analog instruments with computer interfaces, the CPS was designed from the ground up as a digital system.

The CPS used the Stoelting instrument for recording data, with skin conductance as its electrodermal measure — a distinction from other manufacturers that used skin resistance [30]Verified Evaluating Polygraph Data - National Research Council / National Academies Press
Confirms Stoelting uses CPS developed by Scientific Assessment Technologies based on University of Utah research; notes Stoelting records skin conductance; documents CAPS and CPS development. The National Research Council, in its comprehensive 2003 review of polygraph technology, confirmed that Stoelting's CPS system used scientifically validated algorithms for evaluating physiological data [30]Verified Evaluating Polygraph Data - National Research Council / National Academies Press
Confirms Stoelting uses CPS developed by Scientific Assessment Technologies based on University of Utah research; notes Stoelting records skin conductance; documents CAPS and CPS development.

The development of CAPS and CPS was accompanied by complementary advances in computerized scoring. In 1993, statisticians at Johns Hopkins University Applied Physics Laboratory completed PolyScore, software that used sophisticated mathematical algorithms to analyze polygraph data [29]Verified Comprehensive History of the Polygraph - 90210 Polygraph
Confirms Kircher and Raskin developed CAPS in 1988, PolyScore completed at Johns Hopkins in 1993, and validated algorithms exceeded 98% accuracy. Validated algorithms demonstrated accuracy rates exceeding 98% in quantifying physiological data from polygraph examinations [29]Verified Comprehensive History of the Polygraph - 90210 Polygraph
Confirms Kircher and Raskin developed CAPS in 1988, PolyScore completed at Johns Hopkins in 1993, and validated algorithms exceeded 98% accuracy.

The CPS Elite: Fourth-Generation Technology

Today, Stoelting produces the CPS Elite — the fourth generation Computerized Polygraph System [31]Verified CPS Elite Polygraph Systems - Stoelting
Confirms CPS Elite is the fourth generation CPS, the only polygraph with built-in LCD touchscreen, 360 samples/second sampling rate, CPS Fusion software features, and multiple sensor options. The Elite is the only polygraph unit with a built-in display — a full-color LCD touchscreen that provides examiners with active feedback [31]Verified CPS Elite Polygraph Systems - Stoelting
Confirms CPS Elite is the fourth generation CPS, the only polygraph with built-in LCD touchscreen, 360 samples/second sampling rate, CPS Fusion software features, and multiple sensor options. What is shown on the screen is mirrored from the CPS Fusion software on the examiner's computer, allowing channel selection and sensor verification without leaving the subject [31]Verified CPS Elite Polygraph Systems - Stoelting
Confirms CPS Elite is the fourth generation CPS, the only polygraph with built-in LCD touchscreen, 360 samples/second sampling rate, CPS Fusion software features, and multiple sensor options.

The Elite offers examiners unprecedented flexibility, with the choice of traditional mechanical pneumos or electronic pneumos for respiration recording, and the option to measure electrodermal activity using either skin conductance or skin resistance [31]Verified CPS Elite Polygraph Systems - Stoelting
Confirms CPS Elite is the fourth generation CPS, the only polygraph with built-in LCD touchscreen, 360 samples/second sampling rate, CPS Fusion software features, and multiple sensor options. The system records at 360 samples per second — providing more data points for superior scoring accuracy [31]Verified CPS Elite Polygraph Systems - Stoelting
Confirms CPS Elite is the fourth generation CPS, the only polygraph with built-in LCD touchscreen, 360 samples/second sampling rate, CPS Fusion software features, and multiple sensor options. Movement can be monitored from seat, arms, feet, and masseter muscle sensors, each tracked independently [31]Verified CPS Elite Polygraph Systems - Stoelting
Confirms CPS Elite is the fourth generation CPS, the only polygraph with built-in LCD touchscreen, 360 samples/second sampling rate, CPS Fusion software features, and multiple sensor options.

The CPS Fusion software features scientifically validated scoring algorithms, automatic report generation, dynamic importing capabilities, and an integrated multilingual user interface supporting English, Korean, Spanish, and Russian [31]Verified CPS Elite Polygraph Systems - Stoelting
Confirms CPS Elite is the fourth generation CPS, the only polygraph with built-in LCD touchscreen, 360 samples/second sampling rate, CPS Fusion software features, and multiple sensor options. The Elite can also be updated remotely to receive new hardware and software features [31]Verified CPS Elite Polygraph Systems - Stoelting
Confirms CPS Elite is the fourth generation CPS, the only polygraph with built-in LCD touchscreen, 360 samples/second sampling rate, CPS Fusion software features, and multiple sensor options. The CPSpro has been officially replaced by the Elite as Stoelting's flagship product [32]Verified CPS Elite - CPSpro Replacement Notice
Confirms the CPSpro has been officially replaced with the CPS Elite as Stoelting's flagship polygraph system.

Global Reach and Current Operations

Stoelting's present-day headquarters are located at 620 Wheat Lane in Wood Dale, Illinois [2]Verified Stoelting Co. - About Us
Confirms company history from Chicago Laboratory Supply and Scale Co. founding in 1886, dominance of American psychology apparatus market 1903-1943, St. Louis Exposition medals, and current Wood Dale, Illinois headquarters. The company operates multiple divisions covering neuroscience, psychological testing, and polygraph instruments [33]Verified Stoelting Co. LinkedIn Profile
Confirms Stoelting Co. is headquartered in Wood Dale, IL, founded 1886, with Neuroscience division offering stereotaxic instruments and ANY-maze software. The neuroscience division offers world-renowned stereotaxic instruments and ANY-maze behavior tracking software [33]Verified Stoelting Co. LinkedIn Profile
Confirms Stoelting Co. is headquartered in Wood Dale, IL, founded 1886, with Neuroscience division offering stereotaxic instruments and ANY-maze software.

Stoelting's polygraph instruments and accessories are used by law enforcement agencies in the United States and internationally, including in Korea, Canada, Russia, Hungary, Turkey, Australia, South Africa, and Venezuela [34]Verified Stoelting Co. - Yellow Pages Business Profile
Confirms Stoelting provides instruments used by law enforcement in the US, Korea, Canada, Russia, Hungary, Turkey, Australia, South Africa, and Venezuela. The company continues to produce psychological assessments including the Leiter-3, Merrill-Palmer-Revised, and Stroop Color & Word Test [35]Verified Stoelting - Wikipedia
Confirms Stoelting produces psychological assessments including Leiter-3, Merrill-Palmer-Revised, and Stroop Color & Word Test, as well as polygraphs.

The global reach of Stoelting instruments reflects the worldwide expansion of polygraph testing. Countries around the world continue to adopt and expand their polygraph programs. Lithuania's Defence Ministry, for example, recently proposed expanding polygraph testing for national security purposes [36]Verified Lithuanian govt in favor of polygraph tests for risky aliens, company business reps
Documents Lithuania's Defence Ministry proposal to expand polygraph testing for national security purposes, demonstrating continued international demand for quality polygraph instruments. Similarly, our article on polygraph testing in Rwanda illustrates the global reach of modern polygraph technology, while the Soviet Polygraph Program documents the history of polygraph adoption in Russia.

Stoelting vs. the Keeler Polygraph Tradition

Stoelting and the Keeler Polygraph were manufactured by different companies operating in the same city. Leonarde Keeler's instruments were produced by Associated Research, Inc., a Chicago firm established in 1936 by James F. Inman [11]Verified Polygraph - National Museum of American History (Associated Research)
Confirms Associated Research, Inc. was the manufacturer of Keeler polygraphs, established in Chicago in 1936 by James F. Inman (1902-1959). While Keeler is credited with co-inventing the modern polygraph and patenting his instrument in 1939 [37]Verified Leonarde Keeler - Wikipedia
Confirms Keeler born 1903, moved to Chicago to work at Northwestern's SCDL, patented polygraph in 1939, Stoelting developed its own independent line that would ultimately outlast the Keeler instruments.

Keeler moved to Chicago in 1930 to work at Northwestern University's Scientific Crime Detection Laboratory, where he brought the lie detector to prominence [38]Verified Comprehensive History of the Polygraph - Polygraph UK
Confirms Reid's CQT developed in 1947, Backster's ZCT, Kircher & Raskin developed CAPS, and validated algorithms exceeded 98% accuracy. After Keeler's death in 1949, the polygraph manufacturing landscape consolidated around Stoelting and Lafayette as the two primary analog polygraph manufacturers [12]Verified A History of Polygraph Digitization
Confirms Lafayette and Stoelting were the two primary analog polygraph manufacturers who deployed computer systems. Both companies would later deploy computerized systems that transformed the profession.

The parallel development of these Chicago-based polygraph traditions — Keeler's instruments through Associated Research and Stoelting's independent line — created a competitive environment that drove innovation throughout the mid-20th century.

A Century of Polygraph Transformation

Stoelting's history mirrors the broader transformation of polygraphy over the past century. The polygraph profession has undergone a significant shift from intuitive-based practice toward evidence-based practice [26]Verified The Centennial Introspection Project: 100 Years of Polygraph Practice
Documents the polygraph profession's shift from intuitive-based to evidence-based practice over its first century. Researchers have identified several primary transformations that fundamentally altered the trajectory of the polygraph profession from its origins in early 20th century American law enforcement to its current international status [39]Verified A Hundred Years of Polygraphy: Some Primary Changes and Related Issues
Identifies several primary transformations that fundamentally altered the trajectory of the polygraph profession from its origins to its current international status.

Key milestones in this transformation include the evolution from basic lie detection methods to validated testing techniques with computerized scoring systems and standardized practices [27]Verified Foremost Changes in Polygraph in Last 100 Years
Identifies key transformations including evolution from basic lie detection to validated testing techniques with computerized scoring. Stoelting's instruments were central to many of these advances — from the analog Deceptograph that standardized military polygraph testing, to the CAPS system that introduced algorithmic analysis, to the CPS Elite that represents the state of the art.

For a deeper exploration of the early science that preceded these technological advances, see our article on polygraph in the 1910s and Marston's Harvard experiments.

Museum Collections and Historical Preservation

The enduring significance of Stoelting's contributions to polygraph technology is reflected in the preservation of its instruments in major museum collections. The Smithsonian National Museum of American History holds a Stoelting Deceptograph in its permanent collection, with detailed catalog records documenting the instrument's provenance and specifications [21]Verified Deceptograph - Smithsonian National Museum of American History
Confirms Stoelting Deceptograph held in permanent Smithsonian collection with inscription from C. H. Stoelting Co., Chicago. The Smithsonian also holds trade catalogs from C.H. Stoelting Co. that document the company's full range of scientific instruments [1]Verified Stoelting - Smithsonian National Museum of American History Collection
Confirms Christian Hans Stoelting (1865-1943) was a German immigrant who founded Chicago Laboratory Supply and Scale Co. in 1886, renamed C.H. Stoelting Co. by 1903, received 1918 U.S. Navy contract, and holds trade catalogs in Smithsonian collection.

The Henry Ford Museum preserves a Stoelting Polyscribe (Model 22770) from 1974–1977 in its permanent collection [25]Verified Polyscribe Model 22770 - The Henry Ford Museum Collection
Confirms the Stoelting Polyscribe (1974-1977) is held in The Henry Ford Museum permanent collection, recognizing the world's first all-electronic polygraph as a landmark innovation in American technology. These museum holdings ensure that future generations of researchers and historians can study the instruments that shaped the polygraph profession.

For professionals in the field today, understanding this heritage provides valuable context for evaluating modern instruments and techniques. Our guide on how polygraph services work explains how today's examiners use the descendants of these historic instruments.

Stoelting's Impact on Modern Polygraph Practice

Stoelting's influence on modern polygraph practice extends well beyond instrument manufacturing. The company's collaborations with researchers at the University of Utah produced the algorithmic scoring systems that are now considered essential to professional polygraph practice. The CPS system developed by Kircher and Raskin remains the foundation of Stoelting's scoring technology [30]Verified Evaluating Polygraph Data - National Research Council / National Academies Press
Confirms Stoelting uses CPS developed by Scientific Assessment Technologies based on University of Utah research; notes Stoelting records skin conductance; documents CAPS and CPS development.

The company's instruments helped establish standards for physiological recording that other manufacturers eventually adopted. Stoelting's approach of recording skin conductance (rather than skin resistance) for the electrodermal channel has been recognized by researchers as a scientifically sound methodology [30]Verified Evaluating Polygraph Data - National Research Council / National Academies Press
Confirms Stoelting uses CPS developed by Scientific Assessment Technologies based on University of Utah research; notes Stoelting records skin conductance; documents CAPS and CPS development.

As polygraph technology continues to evolve, Stoelting remains at the forefront of innovation. The company's 140-year tradition of quality engineering — from the psychological testing apparatus of the late 19th century to the CPS Elite of today — represents one of the longest continuous threads in the history of scientific instrumentation. Understanding the non-deceptive response pattern and other diagnostic concepts used in modern polygraph testing requires the kind of precise instrumentation that Stoelting has been perfecting for nearly a century and a half.

For those preparing for a modern polygraph examination using Stoelting equipment, our preparation guide provides practical advice. The Stoelting instruments described in this article have also been used in Canadian RCMP polygraph programs and are subject to U.S. export control regulations when sold internationally.