EDITORIAL GUIDE
~5 min read

How to Evaluate UAP Evidence — A Researcher's Guide to the Evidence Hierarchy

Not all UAP evidence is equal. A single witness report with no corroborating sensor data occupies a fundamentally different evidential position than a case documented by multiple military radar systems, airborne FLIR footage, and on-the-record congressional testimony under oath. Understanding how to place individual pieces of evidence in a hierarchy — and how the highest-evidential cases in the archive differ from the lowest — is the core skill of UAP research. This guide explains the evaluation framework used by professional analysts and how it applies to the cases in this archive.

Tier 1 Evidence — Multi-Sensor, Multi-Platform, Corroborated

The highest-evidential UAP cases share a consistent structure: the observation was recorded by multiple independent sensor systems simultaneously, and those systems were operated by trained personnel on separate platforms who could not have coordinated a false positive. The Nimitz Tic Tac case meets all these criteria: radar track on USS Princeton's SPY-1 Aegis system, airborne FLIR footage from F/A-18 operated by Fravor's wing, visual observation by multiple aircrew, and subsequent independent radar confirmation from the E-2C Hawkeye airborne command aircraft. No single point of failure — sensor malfunction, pilot error, or atmospheric anomaly — can explain all four data streams simultaneously.

Other Tier 1 cases in the archive: the Belgian UFO Wave (NATO radar, F-16 radar lock, ground radar, multiple crew observations), the Tehran 1976 intercept (DIA 'outstanding report' designation, weapons systems failure corroboration, multiple aircraft), and the JAL 1628 Alaska encounter (FAA radar track, multiple independent crew observations, FAA ATC corroboration). The common feature is that these cases were investigated by professional analysts at the time of occurrence who found no prosaic explanation after exhaustive review.

Tier 2 Evidence — Single Sensor or Single Platform, Official Record

Tier 2 cases are documented in official government records with a single sensor type or a single reporting platform. They are part of the archive but lack the multi-source corroboration of Tier 1 cases. The O'Hare Airport 2006 disc is a Tier 2 case: it has radar evidence of a hole that appeared in the overcast (corroborating an object that departed through cloud cover) and multiple credible UAL employee witnesses, but no direct radar track of the object itself and no DoD involvement.

Tier 2 cases are valuable for pattern analysis — multiple Tier 2 cases showing the same behavior profile across different locations builds probabilistic evidence even when no single case is definitive. The PURSUE archive's release of 280+ files is largely Tier 2 material: professionally documented incidents with a single sensor or reporting platform, formally categorized as unresolved, contributing to the statistical pattern.

Tier 3 Evidence — Testimony and Whistleblower Claims

Testimony and whistleblower claims occupy Tier 3 — not because they are unimportant, but because they cannot be independently verified against physical sensor records in the public domain. David Grusch's congressional testimony is the highest-profile Tier 3 evidence in the current archive: his ICIG 'credible and urgent' designation means he presented the claim in good faith with supporting evidence to an Inspector General, but the underlying evidence is classified. The testimony itself is a verifiable primary source; the underlying claims are not independently verifiable.

This does not mean Tier 3 evidence should be dismissed. When Tier 3 testimony is consistent across independent sources who have no access to each other's accounts, and when peripheral elements of the testimony are independently verifiable (as with Bob Lazar's element 115 prediction), the testimony carries more weight. The evidential standard for Tier 3 is: what peripheral, verifiable claims accompany the non-verifiable core claim, and are they accurate?

What 'AARO Unresolved' Actually Means

AARO's case resolution categories are frequently misunderstood. 'Unresolved' does not mean 'confirmed UAP' or 'confirmed non-human origin.' It means: AARO's analysts, after reviewing all available information, could not find a prosaic explanation (known aircraft, balloon, bird, atmospheric phenomenon, sensor artifact) that fits the documented data. This is a negative finding — the absence of a mundane explanation — not a positive confirmation of anything exotic.

The significance of 'unresolved' depends on how thoroughly AARO investigated the case. For high-evidential cases like the Nimitz Tic Tac, 'unresolved' after thorough multi-sensor analysis is highly significant — it means no known technology or natural phenomenon fits the documented behavior. For low-data-quality cases, 'unresolved' may simply mean there wasn't enough information to reach any conclusion. Researchers should weigh 'unresolved' designations by the quality of the underlying data, not treat all unresolved cases as equally significant.

KEY POINTS
  • Tier 1 evidence (multi-sensor, multi-platform, corroborated) is the gold standard: Nimitz, Belgian Wave, Tehran 1976, and JAL 1628 are examples where no single point of failure can explain all data streams simultaneously.
  • Tier 2 evidence (single sensor or platform, official record) is valuable for pattern analysis: multiple Tier 2 cases showing the same behavior profile build probabilistic evidence.
  • Tier 3 evidence (testimony and whistleblower claims) is not dismissible — Grusch's ICIG 'credible and urgent' designation is meaningful — but requires verification of peripheral, testable claims before the non-verifiable core can be evaluated.
  • AARO 'unresolved' means no prosaic explanation was found — a negative finding, not a positive confirmation of non-human origin. Its significance depends on how thoroughly AARO investigated.
  • The most common researcher error is treating a credible witness's testimony as Tier 1 evidence — eyewitness accounts without sensor corroboration are Tier 3 regardless of the witness's credibility and rank.
  • The PURSUE archive's 280+ files are largely Tier 2: professionally documented incidents with official records, contributing to pattern analysis rather than individual case confirmation.
  • Multi-system failure scenarios — all independent sensors failing or being fooled simultaneously — are the standard control test for Tier 1 cases; genuine Tier 1 cases have no multi-system failure explanation.
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