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Polygraphy Is Quackery

Make-believe science yields make-believe security.

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The dirty little secret behind the polygraph is that the "test" depends on trickery, not science. The person being "tested" is not supposed to know that while the polygraph operator declares that all questions must be answered truthfully, warning that the slightest hint of deception will be detected, he secretly assumes that denials in response to certain questions -- called "control" questions -- will be less than truthful. An example of a commonly used control question is, "Did you ever lie to get out of trouble?" The polygrapher steers the examinee into a denial by warning, for example, that anyone who would do so is the same kind of person who would commit the kind of behavior that is under investigation and then lie about it. But secretly, it is assumed that everyone has lied to get out of trouble.

The polygraph tracings don't do a special dance when a person lies. The polygrapher scores the test by comparing physiological responses (breathing, blood pressure, heart, and perspiration rates) to these probable-lie control questions with reactions to relevant questions such as, "Did you ever commit an act of espionage against the United States?" (commonly asked in security screening). If the former reactions are greater, the examinee passes; if the latter are greater, he fails. If responses to both "control" and relevant questions are about the same, the result is deemed inconclusive.

The test also includes irrelevant questions such as, "Are the lights on in this room?" The polygrapher falsely explains that such questions provide a "baseline for truth," because the true answer is obvious. But in reality, they are not scored at all! They merely serve as buffers between pairs of relevant and "control" questions.

The simplistic methodology used in polygraph testing has no grounding in the scientific method: it is no more scientific than astrology or tarot cards. Government agencies value it because people who don't realize it's a fraud sometimes make damaging admissions. But as a result of reliance on this voodoo science, the truthful are often falsely branded as liars while the deceptive pass through.

Perversely, the "test" is inherently biased against the truthful, because the more honestly one answers the "control" questions, and as a consequence feels less stress when answering them, the more likely one is to fail. Conversely, liars can beat the test by covertly augmenting their physiological reactions to the "control" questions. This can be done, for example, by doing mental arithmetic, thinking exciting thoughts, altering one's breathing pattern, or simply biting the side of the tongue. Truthful persons can also use these techniques to protect themselves against the risk of a false positive outcome. Although polygraph operators frequently claim they can detect such countermeasures, no polygrapher has ever demonstrated any ability to do so, and peer-reviewed research suggests that they can't.

Latest News:

Government-controlled Reddit Community for Border Patrol Applicants Bans Discussion of Polygraphs
Talk about polygraphy is now verboten on r/borderpatrolapplicant.

Virginia Polygraph Board Unanimously Rejects CVSA
It appears that CVSA will not be approved for use in the state of Virginia. Co-founder George Maschke Interviewed on Publicly Buzzed Live Stream
On Friday, 15 September 2023, brothers Steve and Dan, the hosts of Publicly Buzzed, a YouTube channel focused on crime, mystery, and comedy, spoke about polygraphs with co-founder George Maschke

Voice-Based "Lie Detector" Marketer Offers $2,000 for Success Stories
In a 29 June 2023 mass emailing addressed to "All CVSA Examiners," NITV Federal Services, which markets a putative "lie detector" called the Computer Voice Stress Analyzer (CVSA), offered $2,000 for any success stories that it accepts for publication on its website.

No, Ted Bundy Didn't Pass a Polygraph "Test"
It is often claimed that notorious serial killer Ted Bundy (1946-1989) passed a polyraph test….

Espionage Act Conviction of Former FBI Intelligence Analyst Kendra Kingsbury Raises Questions About the FBI's Personnel Security Polygraph Program
On Wednesday, 21 June 2023, U.S. District Judge Stephen R. Bough sentenced former FBI intelligence analyst Kendra D. Kingsbury, 50, of Kansas to 46 months in prison to be followed by 3 years of supervised release.

EyeDetect Marketer Converus Spends Hundreds of Thousands of Dollars Lobbying Federal Agencies
Intercept investigative reporter Daniel Boguslaw reports on lobbying efforts by Converus Inc., which is attempting to market its EyeDetect “lie detector” to the federal government.E

Polygraph Statement of Wais Ahmad Ahmadzai
Wais served as a combat interpreter with the U.S. Army in Kandahar province in 2008. In 2017, he re-applied, but this time was branded as a liar during a polygraph screening test, despite telling the truth. He remains in Afghanistan where he and his family are in imminent danger from the Taliban.

A Conversation on Polygraph Policy with U.S. Senate Candidate David C. Graham
On Thursday, 20 October 2022, co-founder George Maschke spoke with David C. Graham, the 2022 Libertarian Party candidate for the United States Senate from the state of Kansas.

Benjamin Lawrence Petty Files Appeal to U.S. Supreme Court
On 23 August 2022, Benjamin L. Petty, acting pro se, filed a petition for a writ of certiorari and motion for leave to proceed in forma pauperis with the United States Supreme Court.

Police Polygraph Operator Jason DiPrima Arrested for Soliciting a Prostitute
On Thursday, 1 September 2022, the Polk County, Florida Sheriff’s Office arrested Jason Matthew DiPrima, 49, of Kingston, Georgia in a sting operation for soliciting a prostitute.

Polygraph Statement of Derek (Arizona Department of Public Safety)
In June 2022, I submitted to a polygraph examination with the Arizona Department of Public Safety, conducted by Northland Investigations and the examiner Daniel Caputo. The experience I had with Northland Investigations, and the examiner Dan Caputo in particular, was the worst experience I have ever had with a law enforcement hiring process in my entire life.

Senate Bill Would Mandate Polygraph Screening of Chinese, Russian, and other Foreign Nationals at the Department of Energy
On Wednesday, 27 July 2022, U.S. senators John Barrasso (R-WY) and Roger Marshall (R-KS) introduced Senate Bill 4634, "A bill to require the Secretary of Energy to administer polygraph examinations to certain foreign nationals with access to nonpublic areas or information of the National Laboratories."

Polygraph Screening Failed to Deter Convicted Sex Offender Luke Michael Churchill from Raping Daughter
On 14 June 2022, the U.S. Department of Justice in a press release announced that Luke Michael Churchill of Wilmington, North Carolina, had been sentenced to 40 years in prison after pleading guilty to a single count of production of child pornography.

Some Bad Advice on Polygraphs from National Security Attorney Sean M. Bigley co-founder George Maschke comments on an article recently published on ClearanceJobs.

Arizona Bans Polygraphs in Law Enforcement Internal Investigations
According to an official news release, Arizona governor Doug Ducey on 25 April 2022 signed into law H.B 2159, a bill introduced by Representative John Kavanaugh that withdraws authorization for the use of polygraphs in law enforcement internal investigations.

Failed my first poly @ 12 weeks pregnant - decided to withdraw from applicant processing
"I applied for a role at the CIA back in June 2021. After a long wait, holidays, etc. I finally reached the poly stage. I went in yesterday for my medical, labs, and poly…."

Polygraph Statement of Rahim
From 2007-2010, I worked as a combat interpreter for the United States Army in Afghanistan. My real name is Mohammad, but the American soldiers with whom I worked called me Rahim.

Confession of White Perpetrator in Brittanee Drexel Missing Person Investigation Clears Black Suspect Who Failed FBI Polygraph
On 25 April 2009, 17-year-old Brittanee Drexel of Chili, New York went missing while on holiday in Myrtle Beach, South Carolina. The investigation of the case dragged on for years and garnered nationwide attention.

Long Shot Los Angeles Mayoral Candidate Craig Greiwe Touts Lie Detector Results
Craig Greiwe, currently favored to lose the 7 June 2022 Los Angeles mayoral primary election by a wide margin, has submitted to a polygraph “test” and is challenging other candidates to also do so, as Travis Schlepp reports for KTLA.

Polygraph Operator Lisa Ribacoff Dodges Questions at Crime Conference
Polygraph operator and American Polygraph Association board of directors member Lisa Ribacoff, who is in business with her father, fraud-tainted celebrity polygrapher and private investigator Dan Ribacoff, was a speaker at the Oxygen Network’s recently concluded CrimeCon 2022 conference in Las Vegas, Nevada.

Halifax Scraps Polygraph Screening of Police Applicants
On Tuesday, 8 February 2022, the regional council of Halifax, the largest municipality of the Canadian province of Nova Scotia, voted to end polygraph screening of applicants for employment with the Halifax Regional Police as of 30 September 2022.

On the Origins of the NSA Polygraph Program
In 1951, the NSA's forerunner organization, the Armed Forces Security Agency, began "voluntary" polygraph screening of civilian applicants for employment. On 6 December 1953, the National Security Agency (NSA) made pre-employment polygraph screening mandatory for civilian applicants....