The Mexican Congress UAP Hearing
On September 12, 2023, Mexican journalist and longtime ufologist Jaime Maussan presented two small, purportedly non-human corpses to Mexico's Congress in Mexico City, in Latin America's first congressional hearing on unidentified anomalous phenomena. Testifying under oath, Maussan described the specimens, allegedly recovered from Peru's Nazca region in 2017, as beings that are "not part of our terrestrial evolution." Retired U.S. Navy pilot Ryan Graves, who attended and testified about his own military UAP sightings, publicly called the presentation "a huge step backwards" and "an unsubstantiated stunt." Mexico's National Autonomous University (UNAM), which Maussan credited with carbon-dating the specimens, publicly clarified it had only assessed their age and drawn no conclusions about their origin. A Peruvian prosecutor's office investigation into related 2017 specimens found they were manufactured from human and animal remains, including altered llama and human bones coated in a synthetic adhesive to simulate skin.
Pictured: the Palacio Legislativo de San Lázaro in Mexico City, seat of Mexico's Chamber of Deputies and site of the September 2023 hearing. This is not a photograph of the presented specimens. ProtoplasmaKid, CC BY-SA 4.0.
Theoretical Alignment
This file substitutes "Fabrication / Hoax" for the Psycho-Social/Mundane category because the leading and, in this file's assessment, established explanation is not misperception of a genuine phenomenon but deliberate physical alteration of real human and animal remains to simulate a non-human appearance, a materially different category from the vast majority of cases in this archive. It retains a token Extraterrestrial weighting only in recognition that this file, like any, cannot claim absolute certainty about a claim's origin without having personally examined the specimens.
Background
The hearing was convened by Mexican Congressman Sergio Gutiérrez Luna as the first session of its kind in Latin America, styled as a public forum on "Fenómenos Aéreos Anómalos No Identificados en México" (Unidentified Anomalous Aerial Phenomena in Mexico). It followed months of anticipation after Maussan publicly previewed the specimens, and drew significant international attention as a rare instance of a national legislature formally engaging with UAP testimony, coming two months after the U.S. House Oversight Committee's own July 2023 hearing featuring David Grusch, Ryan Graves, and David Fravor.
Complete Timeline
| Date | Event |
|---|---|
| 2015 | Maussan promotes an earlier "alien mummy" from Peru, later identified as a mummified human child; the same year he also promotes the "Roswell Slides" (a 1894 museum placard) and the "Metepec creature" (later identified by UNAM as a shaved monkey). |
| 2017 | The specimens later presented to Congress are reportedly recovered near the Nazca region of Peru. |
| 2017 (later) | Peruvian authorities open a forensic investigation into related specimens circulating from the same find. |
| Sept. 12, 2023 | Jaime Maussan presents two specimens to Mexico's Congress under oath, alongside testimony from José de Jesús Zalce Benítez and invited testimony from Ryan Graves. |
| Sept. 13, 2023 | UNAM issues a public statement clarifying its carbon-dating work assessed only the specimens' age, not their origin or authenticity. |
| Sept. 13, 2023 | Ryan Graves publicly criticizes the presentation as "a huge step backwards" and "an unsubstantiated stunt." |
| Sept. 2023 (following days) | Journalists and researchers, including skeptic investigators, publish anatomical analyses concluding the specimens show clear signs of tampering, including altered skulls and missing fingers. |
| Nov. 2023 | Maussan returns to Mexico's Congress with the specimens for further testimony, drawing renewed scrutiny. |
| 2023–2024 | The Peruvian Attorney General's Office's forensic investigation concludes the specimens were manufactured from human and animal (including llama) bones, altered and coated with synthetic adhesive to simulate skin. |
The Presentation
Maussan displayed the two specimens in glass cases before the Mexican Congress, describing them as roughly 1,000 years old and possessing elongated heads, three fingers per hand, no teeth, retractable necks, enlarged brains, and "wide stereoscopic vision." One specimen was said to contain eggs. José de Jesús Zalce Benítez, director of the Scientific Institute for Health of the Mexican Navy, stated that X-rays, 3-D reconstruction, and DNA analysis had been performed. Maussan testified under oath, "These are not mummies," and stated the specimens were carbon-dated by UNAM.
The Retraction: What UNAM Actually Said
UNAM's public clarification, issued the day after the hearing, is one of the case's most important pieces of evidence: the university stated its involvement was limited to radiocarbon dating the samples' age and that it had drawn no conclusions whatsoever about the specimens' biological origin or authenticity. This file treats the gap between what UNAM actually did (date organic material) and what the hearing implied it had done (validate non-human origin) as a textbook example of an authoritative citation being used to imply far more scientific endorsement than was actually given.
The Peru Forensic Finding
The most consequential piece of evidence in this case comes not from Mexico but from Peru, where the Attorney General's Office opened a forensic investigation into specimens connected to the same 2017 find. Investigators concluded the objects were assembled from genuine human and animal remains, including human bones and altered llama skulls substituted for original components, that had been physically modified, including the removal of fingers and replacement of skulls, then coated in an unidentified synthetic adhesive substance to disguise the tampering and simulate skin. This file treats the Peruvian forensic finding as the single strongest piece of evidence in the entire case, directly explaining both the specimens' uncanny "alien" appearance and the physical tampering an independent anatomical review would be expected to detect.
Key Figures
Jaime Maussan
Presented the specimens under oath and testified to their non-human origin; has a documented history of promoting multiple previously debunked claims, including the 2015 "Roswell Slides" and "Metepec creature."
José de Jesús Zalce Benítez
Testified that X-ray, 3-D reconstruction, and DNA analysis had been performed on the specimens; had also participated in Maussan's earlier, similarly debunked 2015 Peru mummy presentation.
Ryan Graves
Testified separately about his own military UAP sightings, then publicly and immediately disavowed the Maussan presentation as damaging to the broader UAP transparency effort.
The Five Observables Assessment
This case does not describe an observed craft or aerial phenomenon, and the Five Observables framework does not meaningfully apply to a claimed physical specimen. This file notes its absence here as itself diagnostic: unlike genuinely disputed sightings in this archive, this case presents no anomalous flight behavior, sensor data, or performance characteristics of any kind to evaluate — only a static physical object whose authenticity is the entire question.
Evidence Assessment
Supporting the Presentation's Sincerity (Not Its Conclusions)
- Maussan testified under legal oath before an official body, a step with genuine, if limited, formal weight regardless of the claim's ultimate accuracy.
- The hearing itself is a confirmed, well-documented institutional event, officially recorded and livestreamed by Mexico's Congress.
Supporting a Deliberate Hoax
- A Peruvian Attorney General's Office forensic investigation found the specimens were manufactured from altered human and animal remains coated in synthetic adhesive.
- UNAM publicly and explicitly denied that its work validated any non-human origin, directly contradicting the hearing's implied framing.
- Jaime Maussan has a documented, repeated history of promoting materials later independently identified as hoaxes, including a near-identical 2015 Peru "alien mummy" claim.
- José de Jesús Zalce Benítez, the presentation's principal scientific validator, had also participated in the 2015 case.
- A prominent, credentialed UAP witness (Ryan Graves) who testified at the same hearing publicly and immediately repudiated the presentation.
Why "Debunked"
This case is rated Debunked because an independent forensic authority (the Peruvian Attorney General's Office) directly examined specimens connected to the same find and concluded they were physically manufactured from altered human and animal remains, and because the scientific institution cited as validating the claim (UNAM) publicly and explicitly denied doing so. This combination — direct forensic contradiction plus a repudiated citation — is a stronger and more specific basis for a Debunked rating than this archive typically requires, exceeding the bar of mere unresolved skepticism that keeps most cases at Disputed.
This file also weighs Jaime Maussan's extensive prior track record of promoting since-debunked claims, and the fact that a credible, independently credentialed UAP advocate present at the same hearing immediately and publicly disavowed the presentation, as corroborating rather than merely circumstantial evidence.
Observer Credibility & Occupational Profile
This case presents an unusually clear credibility split: Jaime Maussan, the central witness, has a decades-long media career but also a specific, repeated pattern of promoting claims later independently debunked, including a near-identical prior hoax; his co-presenter had participated in that same prior hoax. By contrast, Ryan Graves, a credentialed former Navy pilot with an established record of sober UAP advocacy, was present at the same hearing and immediately rejected the presentation's credibility, a rare instance in this archive of one witness's testimony being directly and publicly contradicted by another witness at the very same event.
Historical Precedents & Archive Matches
This case fits a recurring pattern in Jaime Maussan's career, matching prior incidents in this archive including his role in the 1991 Mexico City Eclipse UFO Wave and reflecting the same promotional pattern behind the 2015 "Roswell Slides" and "Metepec creature" hoaxes described in his key-figures profile.
Material Analysis
The two specimens presented to Congress were physical objects, unlike most testimonial cases in this archive, making this one of the rare cases where the central evidence was directly forensically examinable. The Peruvian Attorney General's Office's investigation of related specimens from the same find represents genuine physical/material forensic analysis, not secondhand testimony.
Supporting Continued Documentation (Not Belief)
- This case remains historically significant as the first Latin American congressional UAP hearing and as a documented example of how testimonial and institutional framing can outpace the underlying physical evidence.
Supporting a Conventional (Fraudulent) Explanation
- Direct forensic examination of related specimens found deliberate physical manufacture and alteration of human and animal remains, the strongest category of evidence available to this archive.
The Conventional Explanation Candidate: Manufactured Specimens from Altered Human/Animal Remains
The leading, and this file's assessed, conventional explanation is that the presented specimens were deliberately manufactured objects, assembled from genuine but altered human and llama remains and coated in a synthetic substance to simulate an unfamiliar, non-human appearance, consistent with the Peruvian Attorney General's Office's forensic findings on related specimens from the same 2017 find.
A Documented Pattern, Not an Isolated Incident
This explanation is strengthened, not weakened, by Jaime Maussan's prior 2015 presentation of a nearly identical claim, later identified as a mummified human child, and by the participation of the same co-presenter, José de Jesús Zalce Benítez, in both incidents.
Manufactured Specimens from Altered Human/Animal Remains — Plausibility Rating: CONFIRMED BY INDEPENDENT FORENSIC INVESTIGATION
Related Cases
Confirmed Documents & Official Records
Coverage and archival reference to the official hearing, originally livestreamed on the Mexican Congress's own YouTube channel.
PUBLIC RECORD (freely accessible)Search Government Records Directly
Further Reading — Recommended Literature
The Demon-Haunted World: Science as a Candle in the Dark
A foundational text on scientific skepticism and distinguishing genuine evidence from pseudoscience, directly applicable to evaluating this case.
Watch the Skies! A Chronicle of the Flying Saucer Myth
A skeptical history of the flying saucer phenomenon and its recurring pattern of hoaxes, directly relevant to this case.
UFOs: Generals, Pilots, and Government Officials Go on the Record
A compilation of credentialed testimony, useful contrast for weighing Ryan Graves' credibility against this case's central claim.
UFO: The Inside Story of the US Government's Search for Alien Life Here—and Out There
An extensively researched history of government UAP investigation, providing context for how this hearing compares to more rigorous institutional efforts.
The UFO Experience: A Scientific Inquiry
The foundational text on scientifically rigorous UFO classification and evidence evaluation.
Sources
- "'Alien Corpses' Revealed in Hearing Before Mexican Congress," Snopes. Read online →
- "Alleged Alien Corpses Displayed to Mexican Congress Did Not Convince Scientists," Smithsonian Magazine. Read online →
- "Aliens In Mexico? Not So Fast—Presenters Have History Of Being Debunked," Forbes. Read online →
- "The Alien Mummies Presented to Mexico's Congress," Brian Dunning, Substack. Read online →
- "UFO Whistleblower Balks at Claim: 'Alien Corpses' Revealed in Mexico Called 'Unsubstantiated Stunt,'" Fox News. Read online →
- "'Alien Bodies' Presented in Mexican Congress Panned as 'Stunt,'" KSL.com. Read online →
- "Have 'Alien' Bodies Shown in Mexico Already Been Debunked? What to Know," Newsweek. Read online →
- "Mexico Legislators Hold Hearing on Existence of UFOs, Shown 'Alien' Bodies," Al Jazeera. Read online →
- "Mexico 'Alien Bodies': Those Viral Artefacts Get Lab Tests," BBC News. Read online →
- "UFO Expert Presents 'Alien Corpses' in Mexican Congress," Mexico News Daily. Read online →
- "Alien Bodies Mexican Congress Jaime Maussan," Global News. Read online →
- "Controversial Alien Bodies Return to Mexico's Congress as Expert Testifies Again on Discovery," Euronews. Read online →
- Sagan, Carl. The Demon-Haunted World: Science as a Candle in the Dark. Ballantine Books, 1997.
- Peebles, Curtis. Watch the Skies! A Chronicle of the Flying Saucer Myth. Smithsonian Institution Press, 1994.
- Kean, Leslie. UFOs: Generals, Pilots, and Government Officials Go on the Record. Harmony Books, 2010.
- Graff, Garrett M. UFO: The Inside Story of the US Government's Search for Alien Life Here—and Out There. Avid Reader Press, 2023.
- Hynek, J. Allen. The UFO Experience: A Scientific Inquiry. Da Capo Press, 1998 (orig. 1972).
- "File: Palacio Legislativo de San Lázaro obtenido con dron 02.jpg," ProtoplasmaKid, CC BY-SA 4.0. View file →
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