Appendix D

Governance Decision Language (GDL) Specification

The Governance Decision Language (GDL) defines a declarative model for expressing constitutional governance rules. It separates governance policy from application code, enabling consistent evaluation across different runtimes and programming languages.

Business logic determines what a system intends to do. Governance Decision Language determines whether it is constitutionally permitted to do it.

1. Design Objectives

• Human-readable governance rules.
• Machine-executable evaluation.
• Deterministic outcomes.
• Language-independent semantics.
• Version-controlled governance policies.

2. Decision Model

INPUT
   ↓
Authority Evaluation
   ↓
Evidence Validation
   ↓
Policy Evaluation
   ↓
Risk Assessment
   ↓
Admissibility
   ↓
Decision

3. Core Grammar

RULE 

WHEN
    condition

AND
    condition

THEN
    GO | DENY | PAUSE | ESCALATE | OVERRIDE

4. Example Rules

Rule 1 — Permit Execution

RULE payment_approval

WHEN
    authority == VALID

AND
    evidence == COMPLETE

AND
    policy == PASS

THEN
    GO

Rule 2 — Missing Authority

RULE authority_missing

WHEN
    authority == INVALID

THEN
    DENY

Rule 3 — Human Review Required

RULE high_risk_transaction

WHEN
    risk_score > threshold

THEN
    ESCALATE

5. Evaluation Order

6. Decision Semantics

7. Determinism Requirement

Given identical inputs, identical policy versions, and identical evidence, a conforming GDL engine should produce the same governance decision. This property enables replay, auditing, testing, and reproducibility.

8. Policy Versioning

• Each policy SHOULD have a unique identifier.
• Each policy SHOULD include a semantic version.
• Historical versions MUST remain replayable.
• Runtime evaluations SHOULD record the applied policy version.

Appendix Summary

The Governance Decision Language provides a portable, declarative foundation for constitutional decision making. By expressing governance independently of implementation language, GDL enables interoperable and reproducible runtime evaluation across diverse execution environments.

Next: Appendix E — Constitutional Ledger Specification.