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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:

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 Grew 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....

Former San Jose Police Polygraph Operator Robert E. Foster Pleads No Contest to Fraud Charges, Faces Three Years in Jail
In July 2020, the Santa Clara County, California District Attorney's Office charged Robert E. Foster, then a polygraph operator with the San Jose Police Department, "with using his private security company to commit insurance fraud, tax evasion, wage theft, and about $18 million in money laundering."…

Once Secret CIA Report Reveals Derogatory Information on Polygraph Luminaries Gugas, Barefoot, and Harrelson
A formerly secret CIA report provides derogatory information about three prominent polygraph operators of the mid-20th century. The report was declassified and publicly released pursuant to the President John F. Kennedy Assassination Records Collection Act of 1992.

American Polygraph Association Declines Comment as More Racist Text Messages by Member Daniel Ribacoff Surface
Dirty Cops & PIs blog founder and editor Jeffrey Augustine reports on newly discovered racist text messages attributed to disgraced polygraph operator Daniel Ribacoff

In PR Scramble, New York Metropolitan Transit Authority Abruptly Terminates Business With Fraud-Tainted Polygraph Operator Daniel Ribacoff
Within hours of the New York Daily News' reporting on Long Island polygraph operator Daniel D. Ribacoff's racist text messages, the MTA "canceled all remaining polygraphs that were scheduled to be given by Ribacoff's company until his contract expires in early 2022."

Oklahoma Polygraph Board Absolves Lying Polygraph Operator of Wrongdoing
James R. Kelly appears to have lied for the purpose of concealing evidence in a judicial proceeding. The Oklahoma Polygraph Examiners Board seems not to have a problem with that.

Steve Wilkos Show Kicks Polygraph Operator Dan Ribacoff Off Team
Celebrity polygraph operator Daniel D. Ribacoff, who has been with the tabloid television talk program, The Steve Wilkos Show, since its 2007 debut, is evidently no longer on the "team."

Celebrity Polygraph Operator Dan Ribacoff Sent Racist Text Messages has obtained copies of text messages sent by polygraph operator Daniel D. Ribacoff of New York that, while intended to be humorous, evince a deep-seated contempt of, and disdain for, black people.

CVSA Huckster Charles Humble Files for Bankruptcy from Newly Purchased $1.6 Million Home
On 31 August 2021, Charles Wayne Humble, the man behind the Computer Voice Stress Analyzer (CVSA), a quack device marketed to law enforcement agencies, filed for Chapter 7 bankruptcy on behalf of his company, NITV, LLC.

Light 'Em Up Podcast Interviews Co-Founder George Maschke
Topics discussed include Maschke’s personal experience with the polygraph, the scientific shortcomings of polygraphy, polygraph policy, and countermeasures.

Steve Wilkos Show Guest Who Passed Polygraph Later Confessed to Murdering 15-Month-Old
Jesse Wayne Perkins of Clemmens, North Carolina, has pleaded guilty to first degree murder and been sentenced to life in prison.

Polygraph Statement of Mukhtar Alizay
Statement provided by an Afghan combat linguist who served with the U.S. Marines and U.S. Army Special Forces. He was blacklisted after failing a polygraph test.

Polygraph Statement of an Afghan Combat Linguist
Statement provided by an Afghan combat linguist who suffered a traumatic brain injury while serving with U.S. forces. He was fired after failing a polygraph "test" a month after his injuries, and as a consequence, he has been denied a Special Immigrant Visa.

Former NSA Polygraph Division Chief Says Polygraphs Should Not Be the Deciding Factor in Visa Determinations for Afghan Interpreters
Thomas P. Mauriello, who once headed the NSA's Polygraph Division, tells Newsy national security reporter Sasha Ingber that while he thinks the U.S. government should use polygraphs, they alone shouldn't be the determining factor in decision-making.

Former DoD Polygraph Chief Casts Doubt on Policy of Denying Visas to Afghan Interpreters Based on Polygraph Results
In a report published online on Tuesday, 27 July 2021, Newsy In the Loop presenter Christian Bryant asked national security reporter Sasha Ingber about the plight of Afghan Special Immigrant Visa applicants who have been rejected because they failed a polygraph.

How Did CIA Officer and Serial Sexual Abuser Brian Jeffrey Raymond Get Away With His Crimes for So Long?
On Friday, 23 July 2021, Brian Jeffrey Raymond, who, as previously reported on the blog, was until last year all but certainly a career CIA intelligence officer, pleaded guilty to two counts of sexual abuse and one count of transportation of obscene material in the United States District Court for the District of Columbia. He awaits sentencing and will be required to register as a sex offender for the rest of his life.

CNN on Plight of Afghan Interpreters Terminated for Failing Polygraphs
In a report presented by foreign correspondent Anna Coren, CNN chronicles the plight of Afghan linguists who served with United States forces but have been denied Special Immigrant Visas. Both interpreters showcased in the video report were fired because they failed pseudoscientific polygraph "tests."

Steve Wilkos on Lie Detectors: "Hell No…I Would Never Take One!"
The host of the Steve Wilkos Show is unwilling to eat his own dogfood.

Special Immigrant Visas Should Not Be Denied Based on Polygraph Results
As noted on the blog, the United States is denying Special Immigrant Visas to Afghans who served honorably with U.S. forces merely because they "failed" a scientifically baseless polygraph "test"—once. With U.S. forces completing their withdrawal from Afghanistan by the end of August, the lives of many of these individuals are in grave danger. Please write to President Biden and urge him to reverse this policy.

Complaint Against Polygraph Operator James R. Kelly of Oklahoma
"On 5 July 2021, I filed a complaint (attached) against polygraph operator James R. Kelly with the Oklahoma Polygraph Examiners' Board. This complaint is on the agenda for the board's next quarterly meeting, which is to be held tomorrow, Friday 16 July 2021 at 10:00 in Norman…"

SDPD Adds Questions About Hate Crimes and Biases to Pre-Employment Polygraph Process, Acknowledges 50% Failure Rate
At a meeting of the San Diego City Council's Public Safety and Livable Neighborhoods Committee held on 16 June 2021, Captain Rudy Tai of the San Diego Police Department (SDPD) mentioned that the pre-employment polygraph screening process now includes questioning about hate crimes and racial bias.

New York Metropolitan Transit Authority Police Department Has Polygraph Contract With Daniel Ribacoff's Fraud-Tainted Firm
In a 22 April 2021 YouTube interview with retired NYPD detective Ron Licciardi, polygraph operator Daniel Ribacoff, who is best known for his appearances the lowbrow daytime television talk program, the Steve Wilkos Show, disclosed that he has the contract for administering pre-employment polygraph examinations to New York Metropolitan Transit Authority Police Department applicants.

Personal Statement of a CIA Applicant
A recent applicant for employment with the Central Intelligence Agency shares his or her polygraph experience.

NY Lawsuit Details Alleged Fraud by TV Polygraph Operator Daniel Ribacoff’s International Investigative Group, Surveillance of Actress Leah Remini for Church of Scientology
A recent filing in a New York lawsuit presents overwhelming evidence that a private investigation company run by TV polygraph operator Dan Ribacoff engaged in fraudulent billing practices.

LAPD Polygraph Operator Michael Ward Spins the Truth About Polygraphy
In a public relations video posted to Facebook on 24 April 2020, LAPD polygraph operator Michael Ward explains for applicants the special procedures in place for polygraph screening during the COVID-19 pandemic. He also tells some whoppers.

Racial Discrimination Alleged in New York Metropolitan Transportation Authority Police Polygraph Screening
An applicant for employment with the New York State Metropolitan Transportation Authority Police Department has filed a federal Equal Employment Opportunity Commission complaint in connection with a pre-employment polygraph screening "test" administered by that department.

Part 2 of the Pretend Podcast's Interview with Doug Williams
In season 7, episode 7 (The Lie Detector part 2) of the Pretend true crime documentary podcast, Javier Leiva concludes what is likely the last public interview of the late polygraph critic, Doug Williams.

Remembering Doug Williams
"I knew Doug since before the launching of in 2000. He had generously mailed me copies of news articles and a VHS cassette with interviews in which he had appeared…."

Doug Williams, RIP
It is with deep sadness that we report that longtime polygraph critic Douglas Gene Williams died on Friday, 19 March 2021, after an illness.

Doug Williams Interviewed on the Pretend Podcast
In season 7, episode 6 (The Lie Detector part 1) of Pretend, a true crime documentary podcast, Javier Leiva interviews Doug Williams.

Kyriakos Kotsoglou on Polygraphs in the British Legal System
In episode 102 of the legal podcast Excited Utterance, Vanderbilt University law professor Edward K. Cheng interviews Northumbria University senior lecturer in law Kyriakos N. Kotsoglou about the use of polygraphs in the United Kingdom.

Texas DPS Polygraph School Graduation Ceremony Showcases Law Enforcement's Faith in the Pseudoscience of Polygraphy
On Friday, 12 March 2021, the Texas Department of Public Safety Polygraph School graduated its 29th class….

CIA's "Molly Hale" Lies About Lie Detectors
The CIA provides a false and misleading reply about polygraph screening in response to an inquiry from a prospective applicant.

Dr. Phil Presents Polygraph Operator Gil Witte as a "Countermeasures Expert"
San Diego polygraph operator Guillermo R. "Gil" Witte has appeared on the Dr. Phil show for the first time.

Matt Orchard on "The Lie of the Polygraph"
Matt Orchard of Christchurch, New Zealand addresses the pseudoscience of polygraphy in the latest episode of his YouTube documentary series, Crime and Society.

Apparent CIA Officer Brian Jeffrey Raymond, Charged With Drugging and Sexually Molesting Multiple Women, Evidently Beat the Polygraph
Circumstantial evidence strongly suggests that Raymond was employed by the Central Intelligence Agency and that he beat the polygraph at least once.