The Admiralty (NATO 6×6) system for grading intelligence reports — a two-character code separating source reliability (A–F) from information credibility (1–6). Devised by Director of Naval Intelligence John Godfrey in 1939 to cope with wartime reporting volume, formalised in NATO doctrine (AJP-2.1 / STANAG 2511).
The two axes (assessed independently)
- Source reliability (A–F): based on the source's history of accuracy. A = completely reliable … F = cannot be judged.
- Information credibility (1–6): based on corroboration and logic. 1 = confirmed by independent sources … 6 = no basis to judge / contradictory.
Example: A1 = completely reliable source, confirmed information. E5 = unreliable source, improbable content. The two dimensions are deliberately kept separate — an unreliable source can report confirmed truth (E1), and a reliable source can report doubtful information (B5).
Why it matters
- Gives decision-makers at-a-glance trust cues — commanders instantly know which pieces to weight.
- Enforces a discipline of always asking "how do I know this?" and explicitly noting uncertainty.
- The 6×6 grid is coarse, static and doesn't capture motive/partial access; analysts tend to overweight credibility over reliability, a known cognitive bias.
Relation to the wiki's schema
The wiki's own confidence and contested frontmatter fields extend the Admiralty habit — explicit grading and contradiction-noting on every page — into the knowledge layer.
Related
- The Intelligence Cycle — grading happens during the processing/evaluation stage
- Structured Analytic Techniques — modern complement that addresses Admiralty's limits (bias, alternatives)
- Estimative Language — complementary confidence vocabularies
Historical cases (source detail)
Zimmermann Telegram (1917), Battle of the Atlantic (1943), Falklands (1982) are worked examples in the raw source.