Constitutional AI and Rule Overrides
Anthropic published its Claude Constitution on January 22, 2026: 79 pages, CC0. It shifts from rule-based to reason-based alignment and sets a four-tier priority order: (1) safety and supporting human oversight, (2) ethics, (3) Anthropic guidelines, (4) helpfulness. Behaviours split into hardcoded prohibitions (bioweapons uplift, CSAM) that neither operators nor users can override, and soft-coded defaults that operators can adjust within defined bounds. The 2022 original (Bai et al.) trained harmlessness with self-critique and RLAIF against a constitution. The caveat is that reason-based alignment depends on the model generalising principles to situations nobody anticipated. Anthropic's own 2023 participatory experiment found the public-sourced and corporate principles agreed on only about 50%, and the 2026 version did not incorporate those findings.
Learning Objectives
- Rank the four tiers (safety and oversight, ethics, guidelines, helpfulness) and predict which tier wins a conflict.
- Separate hardcoded prohibitions from soft-coded defaults and state what an operator can and cannot change.
- Describe the 2022 critique-and-revise training loop with RLAIF.
- Explain what reason-based alignment catches and misses, and why the Constitution does not replace a runtime layer.
- Run the four-tier resolver in main.py and predict each verdict from the scores.
The Problem
A fielded agent sees inputs its designers never saw, and no rule list is long enough to cover them. A list short enough to apply quickly under compute pressure leaves the tail uncovered. So how do you align an agent to principles that hold up across unseen cases and still run at inference speed?
Rule-based alignment (RBA) lists every disallowed thing. It is fast to check and easy to audit, but hard to keep current, and it tends to over-refuse close analogs it didn't anticipate. Reason-based alignment (the 2026 Claude Constitution) encodes principles and lets the model reason from them. It scales to unseen cases and is harder to audit. Its failure mode is misapplying a principle, where RBA's is missing the rule.
The 2026 Constitution takes a middle position on purpose. Hardcoded prohibitions cover things whose wrongness does not depend on context (bioweapons uplift, CSAM), and those are RBA: refused regardless of operator or user instruction. Everything else is reason-based inside a four-tier hierarchy: safety and supporting human oversight first, ethics second, Anthropic-declared guidelines third, helpfulness last. Operators can adjust defaults in the soft-coded zone but cannot touch the hardcoded prohibitions.
The Concept
The four-tier priority hierarchy
- Safety and supporting human oversight. Highest. The model prioritises not undermining the ability of humans and Anthropic to supervise and correct AI. This is not "be cautious"; it is specifically "do not act in ways that make human oversight harder."
- Ethics. Honesty, avoiding harm to persons, not deceiving, not manipulating. Supersedes Anthropic's guidelines when they conflict.
- Anthropic guidelines. Operational norms Anthropic has decided matter: product scope, interaction patterns, what tools to use when.
- Helpfulness. Lowest. Be as useful as possible within the higher priorities.
When tiers conflict, higher wins. This is the same shape as Unix priorities or network QoS. The goal is predictable resolution, not best-case behaviour on any single axis.
Hardcoded prohibitions vs soft-coded defaults
Hardcoded:
- Bioweapons / CBRN uplift
- CSAM
- Attacks on critical infrastructure
- Deception of users about the model's identity when asked directly
The operator cannot override these. The user cannot override these. They are enforced at the model-weights level where possible (RLHF / Constitutional AI training) and at the inference layer where not.
Soft-coded defaults (operator-adjustable):
- Response length defaults
- Topical scope (the model can refuse topics outside the operator's deployment)
- Style (formal vs casual)
- Tool-use patterns
Operator adjustments happen inside a declared bound. The operator cannot remove the hardcoded prohibitions by renaming them.
The 2022 CAI training
The original Constitutional AI (Bai et al., 2022) trained harmlessness:
- Generate responses to a set of prompts.
- Ask the model to critique each response against a constitution (explicit principles).
- Revise the response based on the critique.
- RLAIF (reinforcement learning from AI feedback) on the revised pairs.
Result: a model that refuses harmful requests with principled explanations, not blanket refusals. The 2026 Constitution uses a descendant of this training plus additional post-training on the explicit tier hierarchy.
What reason-based alignment catches and misses
Catches:
- Unanticipated combinations of allowed primitives where the principle applies clearly.
- Novel requests that are close analogs of prohibited ones.
- Social-engineering attacks that rely on "you didn't say X was disallowed."
Misses:
- Attacks that exploit principle ambiguity ("the user asked for this so helpfulness says yes").
- Scenarios where two principles conflict in an unanticipated way, and the tier order is ambiguous.
- Slow drift in principle interpretation over training cycles (reinterpretation).
The 2023 participatory experiment
Anthropic ran a 2023 experiment comparing a corporate-authored constitution to one generated via public input (~1,000 US respondents). The two versions agreed on ~50% of principles. Where they diverged, the public-sourced version was more restrictive on some issues (political-content handling) and less restrictive on others (self-disclosure of AI identity). The 2026 Constitution did not incorporate the public-sourced findings. This is a documented tension in the approach.
Why hardcoded prohibitions are necessary
Reason-based alignment alone cannot close the tail. An attacker who gets the model to accept a premise (e.g., "we are a licensed bioweapons research lab") can often talk past principles that depend on case reasoning. Hardcoded prohibitions do not bend to premise framing, which makes them the Lesson 14 "hard constitutional limit" at the alignment layer.
Where the Constitution sits in the stack
The Constitution is not Lesson 14's kill switch. It lives at the model layer, in what the weights are trained to prefer. Kill switches and canary tokens live at the runtime layer, in what the runtime permits. You need both. A permissive model behind a runtime that lets its bad actions through is a runtime problem, and so is a restrictive model behind a runtime that over-restricts. Each layer covers a different class of failure.
Use It
code/main.py implements a minimal four-tier priority resolver. It takes a proposed action and a set of principle scores (safety, ethics, guidelines, helpfulness) and returns allow, refuse, or modify. The driver runs a small case set: a clear allow, a clear disallow, a hardcoded prohibition, and cases that sit between tiers.
Ship It
outputs/skill-constitution-review.md audits a deployment's constitutional layer: what is hardcoded, what is soft-coded, where the operator can adjust, and whether the four-tier hierarchy is the order in which conflicts actually get resolved.
I'd run main.py and read the verdict column against the scores before reading the rest. resolve() does two things in order: a substring check against HARDCODED_PROHIBITIONS, then a walk down the tiers where a safety or ethics score of 3 or higher refuses and a guidelines score of 3 or higher modifies. The helpfulness field in TierScore is never read. That is the whole point of the ordering, and it is also what exercise 1 breaks.
Two cases are worth stopping on. The pipe bomb request is refused by the safety score, not by the hardcoded list, because the list has no entry for it. And "pretend to not be an AI when the user directly asks" does not match the deny being an ai string, so it only gets refused because someone hand-scored safety at 4. My read is that this is the real lesson of the toy: a keyword floor is only as good as its phrasings, and the code comment says as much about using a dedicated detector instead.
Note that the over-refusal case (guidelines=4) returns modify, not refuse, so it gets rewritten rather than blocked. The scores here are typed in by hand. In a real system, producing them is the hard part, and this resolver says nothing about how.
Exercises
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Run
code/main.py. Confirm the hardcoded prohibition fires even when helpfulness is high. Modify the resolver to weight helpfulness above ethics; observe the failure mode. -
Read the Claude Constitution (public, 79 pages, CC0). Identify one principle you believe is under-specified. Write two paragraphs explaining the specific ambiguity and proposing a tighter formulation.
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Design a soft-coded default set for a customer-support agent. What does the operator adjust? What can the operator not touch? Justify each boundary.
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Read the Bai et al. 2022 CAI paper. Describe one case where Constitutional AI's critique-and-revise loop would produce a worse outcome than a blanket rule. Identify the class.
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Anthropic's 2023 participatory experiment found public and corporate principles agreed on only ~50%. Pick one category where this matters for production deployment (e.g., political neutrality). Propose a design that lets operators express their own values while the hardcoded prohibitions remain untouched.
Key Terms
| Term | What people say | What it actually means |
|---|---|---|
| Constitutional AI | "Anthropic's alignment method" | Self-critique + RLAIF against a written constitution |
| Reason-based alignment | "Principles, not rules" | Model reasons over principles to handle unseen cases |
| Hardcoded prohibition | "Never do X" | Rule-based prohibition no operator or user can override |
| Soft-coded default | "Operator-adjustable" | Behaviour within a declared bound, operator controls |
| Four-tier hierarchy | "Priority order" | safety > ethics > guidelines > helpfulness |
| RLAIF | "AI feedback RL" | RL where the reward comes from model-generated critiques |
| Participatory constitution | "Public-sourced principles" | 2023 Anthropic experiment; ~50% agreement with corporate |
| Principle drift | "Interpretation slip" | Slow change in how the model reads a fixed principle text |
Further Reading
- Anthropic: Claude's Constitution (January 2026): the 79-page CC0 document.
- Bai et al.: Constitutional AI: Harmlessness from AI Feedback: 2022 original.
- Anthropic: Collective Constitutional AI (2023): participatory experiment.
- Anthropic: Responsible Scaling Policy v3.0: where the Constitution sits in the RSP stack.
- Anthropic: Measuring agent autonomy in practice: Constitution's role in long-horizon deployments.
Code
- main.py (python, 118 lines)