A former Oklahoma City police officer was indicted Thursday on accusations of teaching people to cheat on lie detector tests, the government announced Friday.

The 69-year-old Norman, Oklahoma, man is the owner of Polygraph.com and charged customers thousands of dollars for instructions on how to beat lie detector tests administered for federal employment suitability assessments, federal security background investigations, and internal federal agency investigations, court documents show.

According to the five-count indictment [PDF] lodged against Douglas Williams:

The purpose of the scheme was to defraud the United States and to obtain and maintain positions of Federal employment for Williams' customers for which they did not qualify, and the salary attendant to such positions, through materially false and fraudulent statements and representations. A further purpose of the scheme was for Williams to enrich himself by assisting his customers—including, among others, Federal job applicants, applicants for Federal security clearances, and individuals under investigation by Federal law enforcement agencies—in deceiving the Federal government in order to obtain or maintain positions of Federal employment for which Williams' customers did not qualify.

Polygraph machines, invented in 1921, are notoriously unreliable, and evidence from them is rarely admitted in court. Online talk about how they can be beat is not unusual, and it has even been discussed in the Ars forums.

Prosecutions of this type are rare. One of the last ones occurred in 2013 when an Indiana man, Chad Dixon, was imprisoned for similar accusations of coaching federal employment applicants—including intelligence-community prospective employees—to beat the lie detector. Dixon, 35, was sentenced to eight months in prison in connection to accusations that the sentencing judge acknowledged amounted to a "gray area" of First Amendment speech and the crime of teaching somebody to lie on a government polygraph.

Williams did not immediately respond for comment. But on a YouTube video posted on the Polygraph.com site, he tells prospective customers that "I can teach you how to pass, nervous or not, no matter what." He also says, "Remember, failing to prepare is simply preparing to fail."

The indictment said that, during a telephone call with an undercover federal agent, Williams said, "I haven't lived this long and fucked the government this long, and done such a controversial thing that I do for this long, and got away with it without any trouble whatsoever, by being a dumb ass."

According to court documents, the authorities said he also told an undercover agent last year:

"I've taught a lot of those guys. In fact, there's a lot of government agents—FBI, Secret Service, NSA, all of those alphabet agencies—that have already retired, that I taught, years ago. And I know what I'm doing, and you will pass with no problem."

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