Owner – Michael Martin

michael martin

GPN owner Michael Martin has been a Forensic Psychophysiologist (polygraph examiner) for 40 years and has completed over 11,500 examinations of all types. Better known as “The Lie Detector Guy” from 1997 to 2002, Michael has appeared over 350 times on national and international television as a polygraph expert. Some of these shows include MSNBC, 20/20, 48 Hours, WNBC News, Fox News, Sci-Fi Channel’s Proof Positive, Discovery Channel’s Mythbusters, Sally Jessy Raphael, Ricki Lake, Maury Povich, Dr. Joy Browne, Forgive or Forget, Morton Downey Jr., Richard Bey, and many more. See below for a list of high profile cases.

Michael has authored two polygraph textbooks, Polygraph Theory © 1994 and PDD Testing for Domestic Issues (A Guide for Examiners) © 2012 , and is available for speaking engagements on the topic of Forensic Psychophysiology or Domestic Issue Polygraph Testing.

Michael is an APA certified and licensed polygraph examiner, and holds memberships in the American Polygraph Association, the Maryland Polygraph Association, the Association for the Treatment of Sexual Abusers,the American Society for Testing and Materials, the British & European Polygraph Examiner’s Association, and the Better Business Bureau (A+ rated). Michael is APA certified to conduct Post-Conviction Sex Offender exams, and has been qualified to testify as a polygraph expert. Michael has also been approved to provide testing (under contract) for the United States Government as well as other government agencies.

Michael received training at the New York School of Lie Detection, the Maryland Institute of Criminal Justice, Lion Investigation Academy, and Rider University. Michael holds an honorary (unearned) Doctor in Psychology, but this title is not intended to convey or imply that Martin is a physician, psychologist or psychiatrist. Michael is an instrument-rated private pilot and flies his Mooney 201 anywhere his services are needed.

Michael is available to provide exams at any GPN testing location in which his name appears (see our listings in NY, NJ, PA, CT, VT, DE, and MD) or at any other location worldwide by special quote.


  • Central Park Strangler (a/k/a Preppy Murder) case – In 1988, Michael tested convicted murdered Robert Chambers’ cell mate, Ira Rosenfeld, who claimed Chambers had confessed to Rosenfeld that Chambers had intentionally murdered 18-year old Jennifer Levin in 1986.  Dubbed the “Preppy Murderer,” Chambers was the first defendant to attempt a “rough sex” defense, saying that he accidentally choked Levin to death while having sex with her in Central Park. Results were “deception indicated” to the cell mate having actually received Chambers’ confession.
  • Jon Benet Ramsey murder case – In 1997, Michael was the MSNBC polygraph expert providing commentary and analysis of John and Patsy Ramsey’s independent polygraph exams.
  • Columbine High School Massacre – In 1999, Michael tested three young men suspected by law enforcement of being involved with Eric Harris and Dylan Klebold, who shot 37 people (killing 13) at the Columbine High School in Littleton, Colorado. Results were “no deception indicated” to denial of involvement in the shootings.  Results were provided to local law enforcement who then eliminated these men from being “persons of interest.”
  • Chandra Levy murder case – In 2001, Michael was the Fox News Network polygraph expert providing commentary and analysis of Gary Condit’s polygraph exams concerning Levy’s disappearance.
  • Mike Tyson paternity suit – In 2001, Michael tested a plaintiff in a paternity suit against Mike Tyson claiming she was raped by the boxer in a hotel room. Results were “deception indicated” to the allegation that Tyson has sex with her against her will.
  • Joann Katrinak murder case – In 2002, Michael tested convicted murderer Patricia Rorrer in a defense bid for a new trial. Rorror is serving a life sentence for the 1994 murders of Joann Katrinak and her 3 month old son, Alex.. Results were “deception indicated” to Rorrer having committed the murders.  No new trial has been granted.
  • MythBusters – In 2007, Michael conducted an experiment with the Mythbusters (Discovery Channel) team to test various theories that polygraph could be “beaten” by using certain techniques commonly known as “countermeasures.” The experiment utilized a mock crime scenario whereby some test subjects were guilty and some were innocent (randomly selected). Even though various techniques were used by the guilty parties to defeat the test, Martin was able to correctly identify both the truthful and untruthful examinees with 100% accuracy.
  • White Marlin Open – From 2005 to 2009, Michael provided exclusive polygraph testing for the “World’s Largest Billfish Tournament” held annually in Ocean City MD. This testing was administered to verify that the anglers had not violated any of the tournament rules while catching the prize-winning fish. Top prizes for this tournament were typically in excess of $1 million.
  • Jhon Su Kang murder case – In 2015, Michael tested Tyree Wallace, who had been convicted of killing Jhon Su Kang in 1997 during an armed robbery of Kang’s Philadelphia deli business.  There was no physical evidence to connect Wallace to the crime, and the conviction was based entirely on eyewitness testimony, all of which has been recanted since the trial.  Wallace easily passed his polygraph on the issue of denying involvement in the robbery or in Kang’s death.  As of 2024, after serving 26 years of a life sentence, new efforts are in place to have Wallace’s wrongful conviction vacated.
  • Jamaica Constabulary Force – In 2016, Michael led a team of GPN examiners to Jamaica to screen police recruits for the Jamaica Constabulary Force (JCF).  The team tested 181 applicants, eliminating 88 of them from consideration during the process.
  • Mary Yoder murder case – In 2017, Michael tested Kaitlyn Conley, who was accused of the 2015 poisoning death of Mary Yoder, the mother of Conley’s ex-boyfriend.  In spite of the “no deception indicated” results of the polygraph and alleged inadequate counsel claims, Conley was convicted of killing Yoder.  Appeals are pending.
  • State of Michigan vs. Khaled Mohamed – In 2022, Michael tested Khaled Mohamed, who was charged with a 2018 sexual assault of a woman in a Michigan night club. Mohamed acknowledges that he and the woman engaged in sexual acts on the night in question, but asserts that the acts were entirely consensual. Mohamed, who is not currently living in the United States, wants nothing more than to return to his family in Michigan, and is attempting to prove his innocence. Mohamed passed his polygraph on the issue (no deception indicated) but prosecutors have been reluctant to consider those results, even though there is no physical evidence to support the woman’s claims. This case is ongoing as of June 2023.
  •  Bloods leader shooting death – In 2023, Michael tested the mother of alleged Bloods leader Garland Tyree.  In 2015, Garland Tyree was shot and killed during a shoot-out with police in Staten Island NY.  Tyree had been charged with numerous parole violations following his release from prison after serving 10 years for gun possession.   Michael tested Tyree’s mother, who knew that the guns Tyree was convicted of possessing in 2002 belonged to another gang member, not her son.  Tyree was convicted, even though the guns were found in the other gang member’s home.  To avoid charges, the other gang member told police the guns belonged to Tyree.  Tyree’s mother was present when this other gang member brought the guns to her home in attempt to hide them, but she made him remove the guns.  Tyree’s mother was tested to prove that her son should not have been killed because he should not have been on parole in the first place for a crime he did not commit.  Results were “no deception indicated” to knowing the guns did not belong to Tyree.

Note regarding confidentiality:  The above-mentioned case records are public record, or were intended to be made public. While we do generally consider our client files confidential, such confidentiality is waived when court records are made publicly available or when the results are intended (by our clients) to be released to the public.

Michael can be reached by writing info@polytest.org


Established in 1987, Global Polygraph Network ® is the world’s largest and most trusted polygraph (lie detector) company with services available at hundreds of locations by highly-trained experts all over the world. Avoid “discount” polygraph frauds and “over the phone” testing scams. We only provide real polygraphs by real examiners. Trust our A+ BBB rating, up-front pricing, and written guarantee.