Redaction Taxonomy
A practical coding scheme for Freedom of Information (FOI) redaction analysis
Read the FindingsGlassCase Redaction Taxonomy v0.3 is a practical coding scheme for analysing FOI releases across Australian jurisdictions. It is designed for comparative analysis of redaction patterns and decision quality, not as a substitute for statutory exemption categories.
Optional statutory mapping is provided for Commonwealth FOI to support jurisdiction-specific reporting (see Statutory Mapping below).
Diagnostic tool. This taxonomy is an analyst's coding scheme, not a substitute for statutory interpretation or legal advice. Codes reflect analytical categories, not legal findings. Output should not be treated as evidence of exemption validity or agency conduct.
Use it to code FOI redactions, compare patterns across agencies, and flag decision-quality issues for review.
Substantive Categories
- A1 Direct identifiers: name, address, phone, email, ID numbers
- A2 Indirect identifiers: role + small team context, unique events, rare attributes
- A3 Third-party spill: unrelated people caught in the record
- B1 Physical safety: threats, location risks
- B2 System security: credentials, network details, security controls
- B3 Operational security: routines, response playbooks
- C1 Supplied in confidence: externally provided information
- C2 Business or commercial confidence: procurement, pricing, negotiations
- C3 Inter-agency confidentiality: referral pathways, sharing constraints
- D1 Drafting and iteration: working drafts, tracked changes
- D2 Deliberation material: opinions, advice, recommendations or internal debate forming part of a deliberative process (FOI Act s 47C). Purely factual material is excluded under s 47C(2)(b) unless intertwined with deliberative content.
- D2a Opinion or recommendation · D2b Policy advice or options · D2c Consultation between officials
- D3 Legal material: advice, privilege claims, litigation posture
- E1 Active investigations: integrity processes, HR investigations, ongoing audits
- E2 Law enforcement methods: offences, intelligence, policing methods (FOI Act s 37)
- E3 Operational methods: complaint triage, audit triggers, risk scoring, compliance systems (FOI Act s 47E)
Pattern Flags
These are not reasons for redaction—they're signals of potential decision quality issues worth tracking.
Job titles and dates removed even where identity risk is already eliminated.
The same person's role is disclosed in one email chain but redacted in another.
"Could identify an individual" asserted with no description of what combination creates the risk.
Privacy invoked to remove operational embarrassment—e.g., redacting process errors that do not identify anyone.
Entire paragraphs blacked out where only one sentence contains sensitive detail.
Briefing statistics, background summaries or chronological facts redacted under FOI Act s 47C despite being purely factual material excluded by s 47C(2)(b).
Decision states document is conditionally exempt but no public interest balancing reasoning appears, as required by FOI Act s 11A(5).
Statutory Mapping (Commonwealth)
Freedom of Information Act 1982 (Cth) — Section Reference
This table maps taxonomy categories to the most commonly invoked exemption sections. The FOI Act distinguishes between absolute exemptions (Division 2, pt IV) and conditional exemptions (Division 3, pt IV). Conditional exemptions require a public interest test under FOI Act ss 11A(5), 11B.
| Category | Typical FOI Act Section(s) | Notes |
|---|---|---|
| A — Personal Privacy | FOI Act s 47F |
Conditional; requires "unreasonable disclosure" test + public interest balance |
| B — Safety & Security | FOI Act ss 33, 37 |
Absolute exemptions for national security (FOI Act s 33) and law enforcement/public safety (FOI Act s 37) |
| C — Confidentiality | FOI Act ss 45, 47G |
Breach of confidence (FOI Act s 45, absolute); business affairs (FOI Act s 47G, conditional) |
| D — Decision-process | FOI Act ss 47C, 42 |
Deliberative processes (FOI Act s 47C, conditional); legal professional privilege (FOI Act s 42, absolute) |
| E — Enforcement and Operations | FOI Act ss 37, 47E |
Law enforcement (FOI Act s 37, absolute); operations of agencies including testing, auditing, personnel and operational methods (FOI Act s 47E, conditional) |
Key procedural sections
Redaction logic in practice: apply an exemption under Freedom of Information Act 1982 (Cth) pt IV, apply the public interest test for conditional exemptions (ss 11A(5), 11B), then provide an edited copy where reasonably practicable (s 22) with reasons for decision (s 26).
FOI Act s 11A — Mandatory access rule. Conditionally exempt documents must be released unless access would be "contrary to the public interest."
FOI Act ss 11A(5), 11B — Public interest test for conditional exemptions.
FOI Act s 22 — Access to edited copies with exempt matter deleted. Agencies must provide edited copies where reasonably practicable, with notice of grounds for deletion.
FOI Act s 26 — Reasons for decision. Refusals must state findings on material questions of fact and reasons, including public interest factors for conditional exemptions.
FOI Act s 47 — Trade secrets and commercially valuable information. Commonly invoked alongside FOI Act s 47G for commercial matters; FOI Act s 47 is an absolute exemption while FOI Act s 47G is conditional.
Victoria mapping: State jurisdiction adapter coming in a future release.
Worked Example
Coding a release pack in 6 minutes
Illustrative example. Synthetic ministerial briefing package (12 pages, partial release) modelled on typical disclosure log material.
| Page | Redaction | Stated Reason | Code | Flag |
|---|---|---|---|---|
| 1 | Drafter name, email | FOI Act s 47F | A1 | |
| 3 | Entire recommendation paragraph | FOI Act s 47C | D2 | P5 |
| 4 | "Senior policy officer" title | FOI Act s 47F | A2 | P1 |
| 7 | Contractor pricing schedule | FOI Act s 47G | C2 | |
| 9 | Drafter email (same as p.1) | FOI Act s 47F | A1 | |
| 11 | Name disclosed in footer | not stated | P2 |
How to Use This Taxonomy
- Audit: Code releases to compare patterns across agencies or time. Identify which categories cluster, which flags recur, and where practice diverges from OAIC guidance or FOI Act s 26 decision-letter obligations.
- Review: Use flags to identify over-redaction or inconsistency for internal review requests or OAIC IC review preparation. Flags P3 (mosaic risk without explanation), P4 (category drift), P6 (factual material under deliberative exemption) and P7 (public interest test absent) are particularly useful for challenging weak decisions.
This taxonomy is also suitable for training FOI officers and law students—it provides a shared vocabulary for discussing redaction practice across jurisdictions.
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Version History
v0.3 (March 2026): Doctrinal refinements — D2 sub-codes for deliberative material (s 47C), E category expanded to cover operational methods (s 47E), new pattern flags P6 (factual material under deliberative exemption) and P7 (public interest test absent).
v0.2 (December 2025): Added FOI Redaction Logic Visualiser and improved mobile usability (embedded visualiser + scrollable tables).
v0.1 (December 2025): Initial release. Commonwealth FOI Act mapping only.