Deprecated: Methods with the same name as their class will not be constructors in a future version of PHP; Color has a deprecated constructor in /home/bcph911/public_html/Dec-2017/templates/dream/features/color.php on line 11

Pin It


The Introduction of the Polygraph to Baltimore's Police Department
and the History of the Polygraph in this Country  




The History of the Polygraph Machine

The History of the Polygraph Machine Image 2

In 1902 an inadequate lie detector test was invented by a man named James McKenzie. Later on in the 18th century, 1921, a medical student named

John Larson from the University of California invented the modern polygraph instrument, which was much more accurate in its results than the previous machine.  Although it recorded several different physiological responses, it was not as advanced as the modern polygraph instrument; it measured the subjects pulse rate, blood pressure and respiratory rate and recorded the information on a rotating drum of smoke paper.  In 1925 Leonarde Keeler refined the instrument invented by John Larson; instead of using smoke paper to record changes in the suspects’ reactions, he incorporated ink pens in order to ensure the efficiency of the machine.  In 1938 the machine was further improved by Keeler.  He added another measuring component, galvanic skin resistance.  The polygraph machine continued to advance throughout the years; a man named John Reid introduced the idea of using ‘control questions’ as a means of comparison.  After many years of experimenting with ways to improve the machine, the machine was finally computerized in 1992, this allowed the machine to record the results of the test more efficiently

Leonard Keeler

Leonard Keeler, above all others involved in the history of modern polygraph; can be considered as one of its founders. He was born in 1903 in North Berkeley, California. While in high school, he worked for the Berkeley Police Department for August Vollmer. He assisted John Larson during his early polygraph work. At the time, John Larson was beginning his experiments into detecting deception using his "breadboard" polygraph. A cumbersome instrument, requiring smoked drums, he tested criminal suspects for the Berkeley Police Department. Leonard Keeler was fascinated with the process, a fascination which would turn into a life-long pursuit. He would sneak into the basement of the Berkeley Police Department and "test" his friends using this cumbersome device.

The instrument itself had many drawbacks. It took a half hour to set up. The paper used to record physiological responses had to be smoked and were smudgy and messy. They were very brittle and even with the utmost care, they broke and cracked. The pens on this instrument scratched tracings onto this smoked paper. To preserve the charts once the examination was completed, they had to be shellacked and stored in cans. Although the forerunner of modern polygraph instruments, Keeler found it lacking in many respects. Nicknamed "Shaggy" by the local media, John Larson’s instrument was Leonard Keeler’s first instrument.

Keeler's Second Instrument

"Narde" Keeler and his Emotograph.

After graduating from high school, he enrolled at the University of California at Berkeley in the fall of 1923. He moved shortly after that to enroll in UCLA after Chief Vollmer left Berkeley to accept a new job as the Chief of Police for Los Angeles. Keeler continued to improve his skills in interrogation and lie detection. He had long been disenchanted with the instrument that John Larson used in his work. Cumbersome and messy, Keeler decided to go about creating a new one. Leonard Keeler designed the instrument on paper, using his background in physics, mechanics, and electricity. Vollmer looked at the plans and told Keeler that if he built it, he would "give him a chance to try it out." That’s all Keeler needed. The instrument was conceived and designed with the help of two old friends, Ralph Brandt and Elwood "Doc" Woolsey, high school friends of Leonarde Keeler. The "Three Musketeers" as they called themselves, work between and after classes on this new instrument. When it was finally completed Leonard Keeler called it "The Emotograph." He replaced the smoked paper with an ink polygraph system based on Sir James MacKenzie’s Ink Polygraph which had been used in medical science since the early 1900's. It was smaller, easier to use, August Vollmer described Keeler’s first lie detector as "a crazy conglomeration or wires, tubes, and old tomato cans." It’s first use resulted in a confession in a murder case. That day, Leonard Keeler’s career in lie detection was launched in the press. According to Eloise Keeler, this instrument was destroyed in a fire at Keeler’s residence in 1925.

Keeler's Third Instrument

Western Electro Mechanical Co.

In 1924, LeonardeKeeler’s first handmade polygraph instrument, he called "the Emotograph," was destroyed in a fire at Keeler’s residence. Eloise Keeler reports that before the ashes were cold from this fire, Leonard was busy designing a new instrument.

August Vollmer, Chief of Police of the Berkeley Police Department took Keeler to William Scherer of the Western Electro Mechanical Company. Following Keeler’s plan and written instructions, Scherer developed a mechanical metal bellow, a motor drive, a pneumograph to go around the chest, and a mechanical indicator to mark the graph when a question was asked. The new polygraph was encased in a wooden mahogany box that looked like a traveling case. This was later changed to a metal toolbox, made and custom altered by the Kennedy Tool Box company of Ft. Wayne, Indiana. In the first three months of its creation, they sold sixty to eighty or these new polygraphs to departments in California and all over the country. It was the first mass-produced polygraph or "Lie Detector."

Leonarde Keeler described his new polygraph in an issue of the American Journal of Police Science. He said t The apparatus consisted of three units, one recording continuously and quantitatively the blood pressure and pulse; another giving a duplicate blood pressure pulse curve taken from some other part of the subject’s body and may be utilized for recording muscular reflexes of the arm or leg, and the third unit recording respiration. The paper, perforated on its edges, is drawn by a sprocket feeder roll which is driven by a synchronous motor similar to that used in electric clocks. A differential gear train provides for three speeds and is easily shifted by the movement of a small lever. A ninety-foot roll or paper supplies the recording chart and the curves are recorded by means of a combined lever arm and fountain pen. A sphygmomanometer of the usual dial type is mounted on the panel and connected through a three-way valve to either of the blood pressure systems, providing a means for determining the actual pressure in either system. The metal bellows or tambour stack, which constitutes the reproducing element of each unit, is mounted in a horizontal position below the panel on sliding runs, and is moved forward or backwards (toward or away from the pivot shaft to which is attached the lever arm pen) by means of a rack and pinion, which is controlled by a convenient knob on the panel. The position of the tambour unit in relation to the pivot shaft must be changed according to the pressure utilized in the system. The closed end of the tambour unit is kept at a constant distance from the pivot shaft. A signal magnet actuated by a push button at the end of a convenient length cord is mounted below the recording panel and the connected pen marks on the recording chart. The while apparatus is contained in a carrying case measuring 16 x 8 x 9 inches. All accessories, the lead to the 110v outlet, signal magnet cord, blood pressure cuffs and tubing, and pneumograph are carried in a compartment below the mechanism compartment, The instrument is portable and always ready for immediate use.

Worked independently of Larson, first of the Los Angeles Police Department, and at the University of Southern California, later at Stanford with Professor Miles, and still later at the Institute for Juvenile Research, Leonarde Keeler continued his polygraph research. Records made and filed in Keeler’s office cover more than 30,000 cases. While they were never compiled statistically, they nevertheless showed a high percentage of accuracy and successful results. In 1930, Leonarde Keeler moved to Chicago to work in the Scientific Crime Detection Laboratory at Northwestern University. He became the head of the crime laboratory at the university in 1936. He held that position until 1938 when he entered private business. Leonarde Keeler opened the first polygraph school, known as the "Keeler Institute." He worked as a private polygraph consultant until his death in 1949.

Made from a Kennedy Tool Box Co.

Leonarde Keeler's Personal Instrument

Western Electro Mechanical Prototype

The American Polygraph Historical Society was gifted what is to be believed the prototype of the Western Electro Mechanical Company’s first polygraph. The instrument was built for LeonardeKeeler by William Scherer and used by Leonarde Keeler himself. Over time, Keeler replaced it with many new instruments but saved it for posterity. It was given to Leonard Harrelson, who became Keeler’s confidant and director of the Keeler Polygraph Institute until Keeler’s death in 1949 as a memento of their friendship. Leonard Harrelson presented it to the A.P.H.S. in 1996 for preservation. It has been ravaged by time, and currently mounted in a mahogany box consisting of the top panel and kymograph. It is believed to be the prototype instrument due to its lack of any faceplate or markings on the top panel, nor any evidence that they ever existed. Production instruments would have included these identifiers, but the prototype would not have needed them. Leonard Harrelson reports that this particular instrument was used by Leonard "Nard" Keeler in 1944 to test a group of German POW’s imprisoned at Fort Getty, Rhode Island, to determine their suitability to become police officers in post-WWII Germany.

The Keeler #302

Associated Research

The Model #301 replaced Leonard Keeler’s second polygraph invented in 1925. It was the first polygraph instrument manufactured for Keeler by Associated Research, Inc. of Chicago, Illinois. The Model #302 was introduced in the 1950's and added the "third channel," called a "psychogalvanometer" to the Keeler instrument. This device was manufactured by 'Associated Research' of Chicago, Illinois and utilizes seven batteries, along with an AC power source. It is housed in a steel case with wrinkle finish and chromium trim. The cover is attached to the case with slip hinges allowing the cover to be removed. The chart drive unit is powered by a synchronous motor at speeds of either six or twelve inches per minute. There are four recording pens, the lower pen and its associated control comprise the pulse blood pressure unit, while the longer pen records electrodermal variations. Located above the electrodermal pen is the pen for recording respiration changes, and at the top of the panel is the stimulus marker pen actuated by means of a flexible cable attached at the lower left of the panel. At the center of the instrument panel is a standard sphygmomanometer, used as a guide to proper inflation of the blood pressure cuff. This instrument is not in The Polygraph Museum's Collection. The picture and narrative are courtesy of Ron Decker.

Keeler Model #302C

Associated Research 

The Keeler Model #302 had two modifications, the Model 302B, and Model 302C. This instrument to the left is a Model #302C.

It utilizes seven batteries, along with an AC power source. It is housed in a steel case with wrinkle finish and chromium trim. The cover is attached to the case with slip hinges allowing the cover to be removed. The chart drive unit is powered by a synchronous motor at speeds of either six or twelve inches per minute. There are three recording pens, the lower pen, and its associated controls comprise the pulse-blood pressure unit, while the longer pen records electrodermal variations. At the center of the panel is a standard sphygmomanometer, used as a guide to proper inflation of the blood pressure cuff. - This instrument is in very bad shape and should be used for parts only. We are only using ours for display purposes. 

Keeler Model #304

Associated Research 

In 1952, Russell Chatham was awarded a contract to perform polygraph examinations of employees of the Atomic Energy Facility at Oak Ridge, Tennessee. When awarded the contract, Chatham had Associated Research build instruments for him with his name on them. They were two pen units, a cardiosphygmograph and a pneumograph with an Esterline Angus two speed sprocket drive kymograph. No more than 20 of these instruments were ever manufactured. Fewer than five have survived.

Keeler Model #6303

Associated Research 

The Keeler Model #6303 was a hybrid between the Keller Model #302 and the Model #6308, the first of the PaceSetter Series of polygraphs manufactured by Associated Research. It was a sleeker design than the Model #302 but still used vacuum tubes. Associated research replaced the stainless steel face with a blue acrylic faceplate. It had three separate channels. Pneumograph, cardiograph, and galvanometer. It used a community inking system.

Keeler Model #6308

Associated Research 

The Keeler Model #6308 went into production in the mid 1960's. It was the first of the "Pacesetter" series of polygraphs manufactured by Associated Research. It was a three channel polygraph instrument, designed to record physiological changes of "pulse rate, blood pressure, respiration and skin resistance." The Model 6308 shown here was manufactured by 'Keeler Polygraph' which was a division of 'Associated Research' of Chicago, Illinois. This instrument was used in the late 1960's, initially in the Military, and continued being used until the late 1970's in some States. The Model 6308 is one of the first instruments that can easily be changed from a desk mount to a portable unit without tools. The instruments three separate channels provide a continuous recording of changes in heart rate and blood pressure, breathing rate and skin resistance. It was the first Keeler instrument to use transistors. The G.S.R. component consisted of a pair of finger electrodes, or a hand electrode connected to an input circuit of a direct couple solid-state amplifier with a balanced differential output, feeding the pens. The 6308 utilized a newly designed epoxy encapsulated printed circuits that assured long, trouble-free operation, The Model 6308 is 18" x 9" x 6" and weighs approximately twenty pounds with its accessories. The Model 6308 was sold for $1325.00, which included all required detachable accessories and initial operating supplies consisting of chart paper, ink and conducting jelly. This instrument, serial # 283, was purchased in October of 1969. It was used less than twenty times and then stored until 1998 when donated to the museum.

Keeler Model #6318

Associated Research

The Keeler Model #6318 went into production in the mid-1960's. It was a three channel polygraph instrument, designed to record physiological changes of "pulse rate, blood pressure, respiration and skin resistance." It was identical to the Model 6308, but it could also be operated on battery power. It was equipped with an individual inking system and a sprocket drive kymograph.

Keeler Model #6317

Associated Research 

The Keeler Polygraph Model 6317 shown here was manufactured by the 'Associated Research Company' of Chicago, Illinois. This unit was developed and placed into service during the latter part of 1950, at a time when the most common use for the polygraph was in the field of business for employment screening. During the Korean War, this instrument was utilized by the C.I.A, and again in the early 1960' to polygraph Cuban Nationals to determine if they were spies. This instrument was designed to simulate a piece of luggage, not only to meet F.A.A. regulations but to prevent it from being easily detected throughout the espionage community.

The Model 6317 was one of the first instruments in production utilizing a completely transistorized circuitry. It also boasted itself as being one of the first fully portable polygraph instruments. The Model 6317, along with its sister models developed by 'Associated Research' was in service until the early 1960's. This instrument sold for approximately $1450.00 - This instrument is not in The Polygraph Museum's collection.  Photograph and narrative courtesy of Ron Decker, Polygraph Examiner.

Keeler Model #6328

Associated Research

The Arther II Polygraph 

Specially made for Dick Arther of the National Training Center in New York, and available only to graduates of his polygraph school, the Arther II is a modification of the Keeler Model #6308. It included a GSR component and well as a stimulus marker.

This instrument, serial #41, was manufactured in 1970. It was used between 1971 and 1974 by Louis Seibt, the newly trained polygraph examiner for the Fort Wayne, Indiana Police Department, and retired in 1974 with the purchase of a new Lafayette instrument.

Keeler Model #6338

Associated Research 

The 'Keeler Polygraph' Model 6338 shown here was the first 'Plethysmic Polygraph' manufactured by 'Associated Research' of Chicago, Illinois in the early 1950's. This instrument is the first in the 'Pacesetter Series' which incorporated for the first time an integral photo/optical plethysmograph. The Model 6338 was introduced as a four channel instrument, which recorded simultaneously changes in relative blood pressure, heart rate, pulse wave amplitude, blood volume, oxygenation of the blood, respiration and electrical skin resistance. These reading are obtained by utilizing electronic and pneumatic monitoring. The 6338 required a 115 volt AC current. It weighs twenty- four pounds and is 18" x 11" x 6". The 6338 incorporated newly designed printed circuits and a new inking system where the pens are fed from removable, individually capped ink bottles with colored ink available. The newly designed vent valves have a positive lock to prevent leaks. The design of the cardio cuff, pump bulb assembly and clamp remained basically the same as the 'Pacesetter Series'. There were three different traveling cases available, which confirmed to Federal Aviation requirements at the time for travel. The price for this model was $2325.00. The 'Keeler Polygraph' Model 6338 remained in service through the early 1960's.

1 black devider 800 8 72

Polygraph Research 

In researching the department, we like to find initiation dates, when the Motors Unit, K9, Aviation, Marine or other units got their official start, and sometimes why? Often in getting the initiation date, we'll get a year, sometimes a year and month; we thrive for a full date; Day, Month, Year. So while researching Commissioner Hepbron we came across an article with the headline, "LIE DETECTOR IS UNVEILED," and of course, it led us to believe we would learn when our polygraph unit was initiated. The information we had right off the bat, was that it came from Page 10 of the Baltimore Sun, 29 November 1955.

The opening line was, "City’s first lie detector machine was unveiled yesterday by Police Commissioner James M. Hepbron, for use in the department’s expanded program of Scientific Crime Detection."

Which tells us the unit would have made its debut on Monday, 28 November 1955. The Article went on to provide us with still more clues when in the last sentence, of the first paragraph read,

"A special examining room is under preparation by the rackets division to house the “Lie Box” in the enforcement section on the sixth-floor of the police headquarters building."

Use of various words can be applied like clues at a crime scene. In this case, the author, a witness to the actual 1955 piece of polygraph equipment, a newspaperman, a person whose profession it was that trained him to use words much the way an artist would use a paintbrush. Painting a picture for his reading audience, after viewing the machine searched his database for words to describe best, what it was that he just witnessed. He used the words, "Lie Box" as opposed to, "Lie Case," this let us know the unit was made from a box and not a case. This is telling because there were a few portable polygraph units on the market in 1955.

The Keeler 302, housed in a "factory modified, Kennedy Toolbox," and the Stoelting, which was built in more of an aluminum briefcase looking carrying case. The fact that it was referred to as a "Box" and not a "Case" was the first indication that we were most likely dealing with a Keeler, portable polygraph, and not the Stoelting. As with any investigation, however, you follow the clues, so we continued looking at his words.

Let's look at the weight. The newspaper article described the unit as having a weight of approximately 46 lbs. The Stoelting had manufacture's reported weight of 25 pounds. What increased the weight of these units aside from size, and product components were batteries. The Keeler held six batteries and was listed as having weighed approx 46 lbs. The unit we purchased was lacking the batteries and still came to us with a net shipping weight of 42 pounds, gross weight of 48 pounds.

We needed one of these early "Antique" polygraph units for display in the police museum, but before making a purchase, we went looking to acquire either a Keeler Model 302 or a Stoelting #22055. Obviously, we wanted what was most likely used by the Baltimore Police Department on that Monday, morning in 1955. So using the words as evidence, we did the next thing one would do in an investigation. We spoke to polygraph experts and historians as witnesses. Based on the phrases we had pointed out as having been utilized in the article, the weights described, and the fact that not one of the collectors/experts disagreed with our theories and findings. We believe we were able to purchase the proper machine to most authentically represent an accurate display of the first polygraph machine used by the Baltimore Police.

We believe that by our use of following the clues. The words used the weights described, talking to experts from the polygraph museum, collectors, and polygraph historians. We have gotten to the truth about this lie machine. And that the machine we have on display, best represents the unit witnessed by reporters on that day and used by the Baltimore Police Department in 1955.

So let's talk about the instrument, a Model #302 Keeler polygraph, a unit that was introduced in 1952. At the time they added the "third channel," called a "psychogalvanometer." This machine was manufactured by 'Associated Research' of Chicago, Illinois and utilized six batteries, along with an AC power source. It was built within a steel case.

The case had a brown wrinkle finish paint scheme with slip hinges affixed to the lid allowing for easy removal during examinations. Keeler had his cases custom built by the Kennedy Tool Box company, using their signature paint scheme of that brown crackle finish described earlier.

The machine has a chart drive unit that will run at speeds of either six or twelve inches per minute; it is powered by a synchronous motor. There are three recording styluses, to record pulse, blood pressure, respiration.

In closing, we would like to point out one final line if that newspaper article that drew us to bring this machine to the museum. It was the last subtitle to one of the final paragraphs, and it read,

"The Only One in the State." in that subsection, it reassured much of what was already said but concluded with the following line. "The lie detector, is the only one in the state, it will be made available to other police departments," said Lieut. Grunder head of the polygraph unit. He closed with information about portability, and, he concluded confirming the weight as being approximately 46 pounds.

Lieut. Grunder was a former instructor at the Police Academy; he was assigned to the rackets division and trained five or six assistants to operate the polygraph. He was a lawyer, a graduate of the National Police Academy as well as his having served the Baltimore Police Officer. He was enthusiastic about the possibilities of the polygraph saying, “It’s practically foolproof,” and, “Even if someone attempts to alter the results by moving, coughing or yawning, we can detect their deception, he said.

1 black devider 800 8 72

 It was a long time after the Polygraph that two new techniques came along,
Voice Stress Analysis, and Statement Analysis 


Copies of: Your Baltimore Police Department Class Photo, Pictures of our Officers, Vehicles, Equipment, Newspaper Articles relating to our department and or officers, Old Departmental Newsletters, Lookouts, Wanted Posters, and or Brochures. Information on Deceased Officers and anything that may help Preserve the History and Proud Traditions of this agency. Please contact Retired Detective Kenny Driscoll.

This email address is being protected from spambots. You need JavaScript enabled to view it.

Devider color with motto


How to Dispose of Old Police Items

If you come into possession of Police items from an Estate or Death of a Police Officer Family Member and do not know how to properly dispose of these items please contact: Retired Detective Ken Driscoll - Please dispose of POLICE Items: Badges, Guns, Uniforms, Documents, PROPERLY so they won’t be used IMPROPERLY.

This email address is being protected from spambots. You need JavaScript enabled to view it.

Please contact Det. Ret. Kenny Driscoll if you have any pictures of you or your family members and wish them remembered here on this tribute site to Honor the fine men and women who have served with Honor and Distinction at the Baltimore Police Department.

Anyone with information, photographs, memorabilia, or other "Baltimore City Police" items can contact Ret. Det. Kenny Driscoll at  This email address is being protected from spambots. You need JavaScript enabled to view it. follow us on Twitter @BaltoPoliceHist or like us on Facebook or mail pics to 8138 Dundalk Ave. Baltimore Md. 21222

Copyright © 2002 Baltimore City Police History - Ret Det Kenny Driscoll

Pin It


Copies of: Your Baltimore Police Department Class Photo, Pictures of our Officers, Vehicles, Equipment, Newspaper Articles relating to our department and or officers, Old Departmental Newsletters, Lookouts, Wanted Posters, and or Brochures. Information on Retired or Deceased Officers and anything that may help us to Preserve the History and Proud Traditions of this agency.
Fields marked with * are required
Upload file... Number of files left: 3


    User Login Form