PHASE4_GOVERNANCE_POLICY.md

Phase-4 Governance Policy: Semantic Search (FAISS)

Purpose

Phase-4 introduces optional semantic search capabilities using FAISS to enhance discovery across metadata only associated with publicly released FOIA records.

This policy governs whether, how, and under what constraints Phase-4 may be enabled.

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Scope of Phase-4

Phase-4 MAY include:

• Vector embeddings of metadata fields only (title, agency, date, citation)
• User-initiated semantic similarity queries
• In-memory or user-controlled vector stores

Phase-4 MUST NOT include:

• Full-text document embeddings without explicit review
• Automated crawling or indexing
• Cross-user persistence
• Third-party model training on user data
• Background ingestion or scheduled jobs

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Activation Requirements (ALL REQUIRED)

Phase-4 functionality remains hard-disabled by default.

Activation requires:

1. Legal review approval
2. Hugging Face Trust & Safety concurrence
3. Explicit UI opt-in from the user
4. Clear disclosure of embedding scope and limits
5. Feature flag activation by maintainers

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Data Handling Rules

• No raw PDF content stored by default
• No embeddings persisted beyond session unless user exports
• No cross-session correlation
• No private or sensitive data permitted

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Transparency & Auditability

When enabled, Phase-4 must:

• Log feature activation locally (user-visible)
• Display semantic scope banner
• Provide deterministic reproducibility options
• Include integrity hashes for AI outputs

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Kill-Switch & Rollback

• Feature flag allows immediate global disablement
• No migration required to roll back
• No user data loss on rollback

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Governance Review Cadence

• Initial approval: One-time
• Re-review required for:
  • New data sources
  • New embedding models
  • Persistent storage changes

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Guiding Principle

Semantic discovery must never compromise transparency, provenance, or user consent.