The year Keeler died, the CIA began requiring all incoming employees to take the polygraph test. Two years later, the military polygraph school at Fort Gordon, Georgia was established. The school took over the training of all government polygraph examiners.
In 1951 Larson wrote to Vollmer a five-page letter devoted entirely to the polygraph.19 Larson wanted to set the record straight as to the history of the instrument. Bothered that Keeler's name was more closely associated with the development of the polygraph than his own, Larson was clearing the air. Keeler had been dead seven years and the two men hadn't worked together for twenty-five, but Larson was still bitter. He began the letter with a broad indictment of the field itself:
As you may know, the field is chaotic everyone is talking about the so-called "lie detector." Both Keeler and I independently have always pointed out that there is no "lie detector," but rather a test method which varies with the skill and training of the operator. Because of the many years of exploitation by Lee (C.D. Lee), Keeler and many others, the apparatus was stressed (emphasized) instead of finding out variables which require clinical training. The more we study clinical reactions the more of us agree that there must be a clinical approach. . . . Some time ago a few of us organized to give training to properly qualified teams . . . . A police officer alone is not competent to do this work properly, and because of such tactics so called "lie detectors" have been exploited as psychological third degree. There has not been a proper scientific evaluation by any of the operators. We have found that the error in the interpretation of records may range as high as 40%.
Larson still bristled at the idea that people like Keeler built then patented their polygraph machines: “We are not interested in competing commercially with the many quacks and for that reason I never participated personally in patenting machines.’
The remainder of Larson's letter contains a review of the polygraph's early history in which he reminded Vollmer who had invented the device. Larson reminded Vollmer further that he, Larson, had been the first to apply the polygraph to a real case, at a time when Keeler was a “high school boy in short pants.”
In a 1957 book he co-authored with R. F. Borkenstein, Larson laid out his final thoughts on the polygraph.20 He had come to the conclusion that the polygraph should be used by a team of experts made up of a medical examiner, forensic psychiatrist, and qualified police officer. He wanted the polygraph back into the hands of the scientist, and out of reach of those who would turn it into a business. He believed the polygraph in the wrong hands made it a useless and dangerous instrument. For this reason, he emphasized better qualified examiners rather than more sophisticated machines.
In 1955, Vollmer, now seventy-nine and seriously ill, shot himself to death in his home with his service revolver. That year an anti-polygraph statute in New Jersey, the first of its kind, made it illegal for an employer to require, as a condition of employment or continued employment, a polygraph test.
Larson left the Logansport State Hospital in 1956 to take a job in Nashville as psychiatrist and superintendent of the Tennessee Maximum Security Mental Hospital. Larson's 1957 book was the last thing he published on the polygraph. He was no longer interested in scientific lie detection and had said all he wanted to say about it. He died nine years later at the age of seventy-three.
John Larson was a scientist and a scholar whose brisk manner and lack of tact cost him friends and, in some cases, jobs. His inability to tolerate other people's weaknesses forced him to live his life as a loner. As such, he was always on the outside looking in. He had invented the polygraph, but ended up reading Keeler's headlines. This caused bitterness and more than a little jealousy. Today, Larson is not generally known as the father of the polygraph Keeler is.
Leonarde Keeler was ambitious, dynamic, and energetic. He wasn't a scientist or a scholar. Keeler was a salesman, a promoter, and entrepreneur. He could be charming, and people liked him. Vollmer loved him like a son. During his career he knew and worked with some of the nation's most prominent lawyers, teachers, forensic scientists, criminologists, and crime writers. On occasion he'd sacrifice caution and good sense for a headline and a fast buck. But on the whole, the field of polygraph is indebted to him. He perfected the technology, devised new testing techniques, and found new uses for the instrument. Although he didn't write a book, he published a dozen or so articles. Unlike Larson, he was never a police officer.21
As for Vollmer, he found himself caught between warring protégés. Keeler had captured his heart and Larson his mind. In time, however, Larson's complaints became more like whining and had less and less influence on Vollmer's thinking. To the day he died, Vollmer was mindful of Larson's contribution to law enforcement and was proud of his role in Larson's success. In a letter to V. A. Leonard five months before his death, Vollmer mentioned Larson:22
By all means get the facts from Larson concerning the original research done by that tireless fellow. If my memory serves me correctly, I think that he published articled in ten to twenty magazines. Why not use Larson as a theme for you paper at the Chicago meeting in September?
The polygraph was conceived in Europe but born with Vollmer the midwife, in Berkeley. It was brought up in Chicago by a pair of feuding parents. If Vollmer were alive today, he'd see that the polygraph war is still raging. Examiners are at war with each other, the courts, other forms of scientific lie detection, and with a variety of groups that for one reason or another oppose the instrument. In 1988 Congress virtually outlawed the polygraph as a method of screening job applicants, placing the private or commercial polygraph industry, the industry founded by Keeler, in jeopardy. Vollmer would be pleased to know, however, that although the polygraph hasn't been accepted by the courts, and has almost been legislated out of the private sector, it has been universally accepted by the police as an effective crime-fighting tool. Police investigators, for example, find that the threat of a polygraph test encourages suspects to confess. The war goes on, however, and there are many who want Congress to declare the polygraph contraband, making it a crime for anyone, under any circumstances, to manufacture, possess, or use the instrument.
It's ironic that John Larson, the inventor of the device, would probably be an active supporter of any law that would destroy it.
18. Keeler to Vollmer, January 9, 1945. Bancroft Library.
19. Larson to Vollmer, June 2, 1951. Bancroft Library.
20. Larson, John and R. F. Borkenstein, Academy Lectures on Lie Detection, (Springfield, IL: Charles C. Thomas, 1957).
21. Keeler’s papers are kept at the Bancroft Library. There is a second collection of his papers at the John Crerar Library in Chicago.
22. Vollmer to V. A. Leonard, June 27, 1955. Bancroft Library