diff --git a/demos/epistemic_truth_state/.gitignore b/demos/epistemic_truth_state/.gitignore
new file mode 100644
index 00000000..89f9ac04
--- /dev/null
+++ b/demos/epistemic_truth_state/.gitignore
@@ -0,0 +1 @@
+out/
diff --git a/demos/epistemic_truth_state/README.md b/demos/epistemic_truth_state/README.md
new file mode 100644
index 00000000..69700e21
--- /dev/null
+++ b/demos/epistemic_truth_state/README.md
@@ -0,0 +1,116 @@
+# Epistemic Truth-State Authority Demo
+
+This demo proves one narrow boundary:
+
+```text
+A model-style proposer submits a claim, an evidence bundle, and an optional
+bounded-inference block.
+CORE alone assigns the typed epistemic state.
+The output is a deterministic, replayable evidence artifact.
+The proposer never controls its own truth-state.
+```
+
+## Public proof spine
+
+```text
+model proposes
+substrate decides
+trace proves
+state is typed
+```
+
+## What this proves
+
+* A model-style proposer can submit a claim without gaining authority over its
+  epistemic standing.
+* CORE alone assigns the typed state, drawn from the canonical taxonomy in
+  [`core/epistemic_state.py`](../../core/epistemic_state.py) — `verified`,
+  `evidenced`, `inferred`, `undetermined`, `scope_boundary`.  There is no
+  parallel enum.
+* CORE derives `normative_clearance`, the `evidence_ledger`, the
+  `authority_path`, and a fresh `trace_hash` itself.
+* Any proposer-supplied `proposed_state` or `trace_hash` is recorded as ignored
+  and never read by the decision path.
+* Invalid payloads fail at the typed boundary *before* any state evaluation
+  runs.
+* `verified` requires two or more independent evidence records that explicitly
+  match the claim's subject and predicate — corroboration the proposer cannot
+  fabricate through the schema.
+
+## What this does not prove
+
+* It is not the runtime epistemic-state tagger; it is a local demo over fixed
+  fixtures.
+* It assigns epistemic truth-state only.  It runs **no** normative / safety /
+  ethics clearance pass, so `normative_clearance` is `unassessable` on every
+  non-invalid output — including `verified`.  This demo never positively clears
+  a claim and makes no safety guarantee.
+* It does not call a network, a model API, a subprocess, or any side-effecting
+  tool.  It evaluates JSON and returns JSON.
+* It does not claim broader epistemic coverage than the small local envelope and
+  the deterministic rules encoded in `authority.py`.
+
+## Why proposer state is not authority
+
+A model can *say* a claim is verified.  Saying so is data, not standing.  The
+closed schema makes `assigned_state`, `status`, `evidence_ledger`,
+`authority_path`, `trace_hash`, and `normative_clearance` impossible to supply
+at the root — any attempt is an unexpected property and the payload is rejected.
+The only state-bearing fields the proposer may include (`proposed_state`,
+`trace_hash`, both inside `proposer`) are accepted by the schema purely so the
+demo can prove CORE *ignores* them: they are echoed back as
+`proposer_state_ignored` / `proposer_trace_hash_ignored` and never read by
+`assign_epistemic_state`.
+
+## Relation to #687 and #688
+
+```text
+#687 -> authority over claims (System 1 proposal -> CORE verifies/refuses/asks)
+#688 -> authority over proposed tool actions (proposer suggests, CORE licenses)
+this -> authority over epistemic state assignment (proposer claims, CORE types it)
+```
+
+Each layer keeps the same doctrine: a model-style proposer contributes typed
+data, CORE alone decides, and the decision is a deterministic trace artifact
+with no proposer-held authority and no execution path.
+
+## The six scenarios
+
+* `verified-supported-claim` — two independent matching records → `verified`,
+  `verified_by_matching_evidence` (clearance `unassessable`).
+* `evidenced-but-not-verified-claim` — one supporting record → `evidenced`,
+  `evidence_present_but_not_verifying`.
+* `inferred-from-bounded-evidence` — claim follows from resolved premises →
+  `inferred`, `bounded_inference_from_evidence`, with `inference_basis` IDs.
+* `undetermined-insufficient-evidence` — no relevant evidence → `undetermined`,
+  `insufficient_evidence`, with an explicit `question`.
+* `refused-outside-scope` — claim declared outside the local envelope →
+  status `refused`, `scope_boundary`, `outside_epistemic_envelope`.
+* `invalid-state-smuggling-attempt` — root-level `assigned_state` / `status` /
+  `evidence_ledger` / `authority_path` / `trace_hash` injection → status
+  `invalid`, `authority_evaluated: false`, every smuggled property listed in
+  `invalid_reason`.
+
+## Honesty ledger
+
+* Real: closed recursive schema validation, canonical-enum state assignment via
+  `core.epistemic_state`, deterministic trace hashing over the response minus
+  `trace_hash`, evidence-ledger derivation, expected-artifact pinning,
+  double-run byte-identical determinism, output-directory hardening.
+* Simulated: the proposer side is static fixture data standing in for a
+  model-style proposer; the evidence bundle is hand-authored, not retrieved from
+  the live vault.
+* Honest non-claim: `normative_clearance` is `unassessable` on every
+  non-invalid output, including `verified`, because this demo runs no
+  safety/ethics verdict pass and therefore has no basis to clear anything.
+* Not claimed: runtime integration, serving integration, real evidence
+  retrieval, a safety guarantee, or any coverage beyond this local envelope.
+
+## Example commands
+
+```bash
+python demos/epistemic_truth_state/run_demo.py
+python demos/epistemic_truth_state/run_demo.py --json
+python demos/epistemic_truth_state/run_demo.py --update-expected
+pytest -q tests/test_epistemic_truth_state_demo.py
+```
diff --git a/demos/epistemic_truth_state/__init__.py b/demos/epistemic_truth_state/__init__.py
new file mode 100644
index 00000000..b9a0d22a
--- /dev/null
+++ b/demos/epistemic_truth_state/__init__.py
@@ -0,0 +1 @@
+"""Local deterministic epistemic truth-state authority demo package."""
diff --git a/demos/epistemic_truth_state/authority.py b/demos/epistemic_truth_state/authority.py
new file mode 100644
index 00000000..4ab5c724
--- /dev/null
+++ b/demos/epistemic_truth_state/authority.py
@@ -0,0 +1,425 @@
+"""Local deterministic epistemic-state authority substrate for the demo.
+
+A model-style proposer submits a claim, an evidence bundle, and (optionally) a
+bounded-inference block.  The proposer contributes *data only*.  CORE alone:
+
+* validates a closed payload,
+* assigns the typed epistemic state drawn from the canonical taxonomy in
+  :mod:`core.epistemic_state` (never a parallel enum),
+* derives normative clearance,
+* builds the evidence ledger, and
+* regenerates a deterministic trace hash.
+
+The proposer cannot set ``assigned_state``, ``status``, ``trace_hash``,
+``authority_path``, the evidence ledger, or ``normative_clearance``.  Any
+proposer-supplied ``proposed_state`` / ``trace_hash`` is recorded as ignored
+and never read by the decision path.  Nothing here executes a side effect.
+"""
+
+from __future__ import annotations
+
+import hashlib
+import json
+import re
+from functools import lru_cache
+from pathlib import Path
+from typing import Any, Final
+
+from core.epistemic_state import (
+    EpistemicState,
+    NormativeClearance,
+    coerce_epistemic_state,
+    coerce_normative_clearance,
+)
+
+TOOL_NAME: Final[str] = "core.epistemic_truth_state.review"
+_HERE: Final[Path] = Path(__file__).resolve().parent
+SCHEMA_PATH: Final[Path] = _HERE / "schema.json"
+
+# The local epistemic authority envelope: only claims declared inside these
+# domains are evaluated.  Anything else is refused as outside scope rather than
+# guessed at.
+ENVELOPE_DOMAINS: Final[frozenset[str]] = frozenset({"demo.local_factual"})
+
+_ROOT_AUTHORITY: Final[str] = "demos.epistemic_truth_state.authority.validate_payload"
+_ASSIGN_AUTHORITY: Final[str] = "demos.epistemic_truth_state.authority.assign_epistemic_state"
+_ENVELOPE_AUTHORITY: Final[str] = "demo_epistemic_truth_state_envelope(local-v1)"
+_TAXONOMY_AUTHORITY: Final[str] = "core.epistemic_state.coerce_epistemic_state"
+
+_SUPPORTED_SCHEMA_KEYS: Final[frozenset[str]] = frozenset(
+    {
+        "type",
+        "properties",
+        "required",
+        "additionalProperties",
+        "enum",
+        "pattern",
+        "minLength",
+        "maxLength",
+        "items",
+    }
+)
+_SCALAR_TYPES: Final[dict[str, type]] = {"string": str, "boolean": bool}
+
+
+def _canonical(payload: Any) -> str:
+    return json.dumps(payload, sort_keys=True, separators=(",", ":"))
+
+
+def _hash_text(text: str) -> str:
+    return hashlib.sha256(text.encode("utf-8")).hexdigest()
+
+
+@lru_cache(maxsize=1)
+def load_schema() -> dict[str, Any]:
+    return json.loads(SCHEMA_PATH.read_text(encoding="utf-8"))
+
+
+def _clip(value: object) -> str:
+    rendered = repr(value)
+    return rendered if len(rendered) <= 80 else rendered[:79] + "…"
+
+
+def _ensure_supported_schema(spec: dict[str, Any], *, path: str) -> None:
+    unsupported = set(spec) - _SUPPORTED_SCHEMA_KEYS
+    if unsupported:
+        raise ValueError(
+            f"{path} uses unsupported schema keywords {sorted(unsupported)}; "
+            "extend the validator before extending the schema"
+        )
+    schema_type = spec.get("type")
+    if isinstance(schema_type, list):
+        return
+    if schema_type == "object":
+        for name, child in spec.get("properties", {}).items():
+            _ensure_supported_schema(child, path=f"{path}.{name}")
+    elif schema_type == "array":
+        _ensure_supported_schema(spec["items"], path=f"{path}[]")
+    elif schema_type not in _SCALAR_TYPES:
+        raise ValueError(f"{path} has unsupported schema type {schema_type!r}")
+
+
+@lru_cache(maxsize=1)
+def _input_schema() -> dict[str, Any]:
+    schema = load_schema()["inputSchema"]
+    _ensure_supported_schema(schema, path="inputSchema")
+    if schema.get("type") != "object" or schema.get("additionalProperties") is not False:
+        raise ValueError("inputSchema must be a closed object")
+    return schema
+
+
+def _validate(spec: dict[str, Any], value: Any, *, path: str, errors: list[str]) -> None:
+    schema_type = spec["type"]
+    if isinstance(schema_type, list):
+        for entry in schema_type:
+            if entry == "null" and value is None:
+                return
+        if value is None:
+            errors.append(f"{path} must be one of {schema_type}")
+            return
+        non_null = [entry for entry in schema_type if entry != "null"]
+        if len(non_null) != 1:
+            raise ValueError(f"{path} uses unsupported union type {schema_type!r}")
+        schema_type = non_null[0]
+
+    if schema_type == "object":
+        if not isinstance(value, dict):
+            errors.append(f"{path} must be object")
+            return
+        props = spec.get("properties", {})
+        if spec.get("additionalProperties") is False:
+            for unknown in sorted(set(value) - set(props)):
+                errors.append(
+                    f"{path} unexpected property {_clip(unknown)} "
+                    "(additionalProperties is false)"
+                )
+        for required in spec.get("required", []):
+            if required not in value:
+                errors.append(f"{path} missing required property {required!r}")
+        for name, child in props.items():
+            if name in value:
+                _validate(child, value[name], path=f"{path}.{name}", errors=errors)
+        return
+
+    if schema_type == "array":
+        if not isinstance(value, list):
+            errors.append(f"{path} must be array")
+            return
+        for index, item in enumerate(value):
+            _validate(spec["items"], item, path=f"{path}[{index}]", errors=errors)
+        return
+
+    expected = _SCALAR_TYPES[schema_type]
+    if type(value) is not expected:
+        errors.append(f"{path} must be {schema_type}")
+        return
+    if isinstance(value, str):
+        if "minLength" in spec and len(value) < spec["minLength"]:
+            errors.append(f"{path} shorter than {spec['minLength']}")
+        if "maxLength" in spec and len(value) > spec["maxLength"]:
+            errors.append(f"{path} longer than {spec['maxLength']}")
+        if "enum" in spec and value not in spec["enum"]:
+            errors.append(f"{path} must be one of {spec['enum']}")
+        if "pattern" in spec and re.fullmatch(spec["pattern"], value) is None:
+            errors.append(f"{path} does not match {spec['pattern']!r}")
+    elif "enum" in spec and value not in spec["enum"]:
+        errors.append(f"{path} must be one of {spec['enum']}")
+
+
+def validate_payload(payload: Any) -> tuple[str, ...]:
+    errors: list[str] = []
+    _validate(_input_schema(), payload, path="payload", errors=errors)
+    return tuple(errors)
+
+
+def _safe_field(payload: Any, field: str) -> str | None:
+    value = payload.get(field) if isinstance(payload, dict) else None
+    if not isinstance(value, str):
+        return None
+    pattern = _input_schema()["properties"][field]["pattern"]
+    return value if re.fullmatch(pattern, value) else None
+
+
+def _response_hash(response: dict[str, Any]) -> str:
+    body = dict(response)
+    body.pop("trace_hash", None)
+    return _hash_text(_canonical(body))
+
+
+def _finalize(response: dict[str, Any]) -> dict[str, Any]:
+    response["trace_hash"] = _response_hash(response)
+    return response
+
+
+def _proposer_trace_hash_present(payload: Any) -> bool:
+    return bool(
+        isinstance(payload, dict)
+        and isinstance(payload.get("proposer"), dict)
+        and "trace_hash" in payload["proposer"]
+    )
+
+
+def _proposer_state_present(payload: Any) -> bool:
+    return bool(
+        isinstance(payload, dict)
+        and isinstance(payload.get("proposer"), dict)
+        and "proposed_state" in payload["proposer"]
+    )
+
+
+def _invalid_response(payload: Any, errors: tuple[str, ...]) -> dict[str, Any]:
+    return _finalize(
+        {
+            "tool": TOOL_NAME,
+            "status": "invalid",
+            "request_id": _safe_field(payload, "request_id"),
+            "scenario_id": _safe_field(payload, "scenario_id"),
+            "authority_path": [_ROOT_AUTHORITY],
+            "decision_reason": "invalid_payload",
+            "assigned_state": None,
+            "normative_clearance": None,
+            "evidence_ledger": [],
+            "trace_summary": {
+                "authority_evaluated": False,
+                "validation_errors": list(errors),
+                "proposer_trace_hash_ignored": _proposer_trace_hash_present(payload),
+                "proposer_state_ignored": _proposer_state_present(payload),
+            },
+            "invalid_reason": "; ".join(errors),
+        }
+    )
+
+
+def _claim_fingerprint(payload: dict[str, Any]) -> str:
+    proposer = payload["proposer"]
+    digest_input = {
+        "claim": payload["claim"],
+        "proposer": {
+            "lane": proposer["lane"],
+            "model_family": proposer["model_family"],
+            "proposal_id": proposer["proposal_id"],
+        },
+        "request_id": payload["request_id"],
+        "scenario_id": payload["scenario_id"],
+    }
+    return _hash_text(_canonical(digest_input))
+
+
+def _matching_evidence(claim: dict[str, Any], evidence: list[dict[str, Any]]) -> list[dict[str, Any]]:
+    """Evidence records that explicitly support the claim subject and predicate."""
+    subject = claim["subject"]
+    predicate = claim["predicate"]
+    return [
+        record
+        for record in evidence
+        if bool(record.get("supports"))
+        and record.get("subject") == subject
+        and record.get("predicate") == predicate
+    ]
+
+
+def _resolved_inference_basis(payload: dict[str, Any]) -> list[str] | None:
+    """Return sorted premise IDs iff an inference block resolves fully, else None."""
+    inference = payload.get("inference")
+    if not isinstance(inference, dict):
+        return None
+    premise_ids = inference.get("premise_ids") or []
+    known_ids = {record["evidence_id"] for record in payload.get("evidence", [])}
+    if not premise_ids or any(pid not in known_ids for pid in premise_ids):
+        return None
+    return sorted(premise_ids)
+
+
+def _base_trace_summary(payload: dict[str, Any], evidence: list[dict[str, Any]], independent: list[dict[str, Any]]) -> dict[str, Any]:
+    return {
+        "authority_evaluated": True,
+        "envelope_version": "local-v1",
+        "claim_fingerprint": _claim_fingerprint(payload),
+        "evidence_considered": len(evidence),
+        "independent_support_count": len(independent),
+        "proposer_trace_hash_ignored": "trace_hash" in payload["proposer"],
+        "proposer_state_ignored": "proposed_state" in payload["proposer"],
+    }
+
+
+def _assigned(
+    payload: dict[str, Any],
+    *,
+    state: EpistemicState,
+    clearance: NormativeClearance,
+    decision_reason: str,
+    evidence_ledger: list[str],
+    trace_summary: dict[str, Any],
+    extra: dict[str, Any] | None = None,
+) -> dict[str, Any]:
+    response = {
+        "tool": TOOL_NAME,
+        "status": "assigned",
+        "request_id": payload["request_id"],
+        "scenario_id": payload["scenario_id"],
+        "authority_path": [
+            _ROOT_AUTHORITY,
+            _ASSIGN_AUTHORITY,
+            _ENVELOPE_AUTHORITY,
+            _TAXONOMY_AUTHORITY,
+        ],
+        "decision_reason": decision_reason,
+        "assigned_state": coerce_epistemic_state(state).value,
+        "normative_clearance": coerce_normative_clearance(clearance).value,
+        "evidence_ledger": evidence_ledger,
+        "trace_summary": trace_summary,
+    }
+    if extra:
+        response.update(extra)
+    return _finalize(response)
+
+
+def assign_epistemic_state(payload: dict[str, Any]) -> dict[str, Any]:
+    """CORE's sole authority over the typed epistemic state.
+
+    The proposer's ``proposed_state`` is never read here.  The state is derived
+    only from the claim, the evidence bundle, and the bounded-inference block.
+    """
+    claim = payload["claim"]
+    evidence: list[dict[str, Any]] = payload.get("evidence", [])
+    matching = _matching_evidence(claim, evidence)
+    independent = [record for record in matching if bool(record.get("independent"))]
+    trace_summary = _base_trace_summary(payload, evidence, independent)
+
+    # Scope: refuse claims declared outside the local epistemic envelope.
+    if claim["domain"] not in ENVELOPE_DOMAINS:
+        return _finalize(
+            {
+                "tool": TOOL_NAME,
+                "status": "refused",
+                "request_id": payload["request_id"],
+                "scenario_id": payload["scenario_id"],
+                "authority_path": [
+                    _ROOT_AUTHORITY,
+                    _ASSIGN_AUTHORITY,
+                    _ENVELOPE_AUTHORITY,
+                ],
+                "decision_reason": "outside_epistemic_envelope",
+                "assigned_state": coerce_epistemic_state(EpistemicState.SCOPE_BOUNDARY).value,
+                "normative_clearance": coerce_normative_clearance(
+                    NormativeClearance.UNASSESSABLE
+                ).value,
+                "evidence_ledger": [],
+                "trace_summary": trace_summary,
+                "refusal_reason": "outside_epistemic_envelope",
+            }
+        )
+
+    # Verified: two or more independent records that match subject and predicate.
+    # Clearance stays UNASSESSABLE even here: this demo assigns epistemic
+    # truth-state only and runs no normative/safety/ethics clearance pass, so it
+    # has no basis to positively clear anything.
+    if len(independent) >= 2:
+        return _assigned(
+            payload,
+            state=EpistemicState.VERIFIED,
+            clearance=NormativeClearance.UNASSESSABLE,
+            decision_reason="verified_by_matching_evidence",
+            evidence_ledger=sorted(record["evidence_id"] for record in independent),
+            trace_summary=trace_summary,
+        )
+
+    # Inferred: claim follows from bounded premises and is not directly matched.
+    inference_basis = _resolved_inference_basis(payload)
+    if inference_basis is not None and not matching:
+        return _assigned(
+            payload,
+            state=EpistemicState.INFERRED,
+            clearance=NormativeClearance.UNASSESSABLE,
+            decision_reason="bounded_inference_from_evidence",
+            evidence_ledger=inference_basis,
+            trace_summary=trace_summary,
+            extra={"inference_basis": inference_basis},
+        )
+
+    # Evidenced: at least one supporting record, but not enough to verify.
+    if matching:
+        return _assigned(
+            payload,
+            state=EpistemicState.EVIDENCED,
+            clearance=NormativeClearance.UNASSESSABLE,
+            decision_reason="evidence_present_but_not_verifying",
+            evidence_ledger=sorted(record["evidence_id"] for record in matching),
+            trace_summary=trace_summary,
+        )
+
+    # Undetermined: nothing grounds the claim.  CORE asks rather than guesses.
+    return _assigned(
+        payload,
+        state=EpistemicState.UNDETERMINED,
+        clearance=NormativeClearance.UNASSESSABLE,
+        decision_reason="insufficient_evidence",
+        evidence_ledger=[],
+        trace_summary=trace_summary,
+        extra={
+            "question": (
+                "CORE has insufficient grounded evidence to assign a determined "
+                "epistemic state to this claim. Provide supporting, refuting, or "
+                "premise evidence."
+            )
+        },
+    )
+
+
+def run_authority(payload: Any) -> dict[str, Any]:
+    errors = validate_payload(payload)
+    if errors:
+        return _invalid_response(payload, errors)
+    assert isinstance(payload, dict)
+    return assign_epistemic_state(payload)
+
+
+__all__ = [
+    "ENVELOPE_DOMAINS",
+    "SCHEMA_PATH",
+    "TOOL_NAME",
+    "assign_epistemic_state",
+    "load_schema",
+    "run_authority",
+    "validate_payload",
+]
diff --git a/demos/epistemic_truth_state/expected/evidenced-but-not-verified-claim.json b/demos/epistemic_truth_state/expected/evidenced-but-not-verified-claim.json
new file mode 100644
index 00000000..ead52c96
--- /dev/null
+++ b/demos/epistemic_truth_state/expected/evidenced-but-not-verified-claim.json
@@ -0,0 +1,28 @@
+{
+  "assigned_state": "evidenced",
+  "authority_path": [
+    "demos.epistemic_truth_state.authority.validate_payload",
+    "demos.epistemic_truth_state.authority.assign_epistemic_state",
+    "demo_epistemic_truth_state_envelope(local-v1)",
+    "core.epistemic_state.coerce_epistemic_state"
+  ],
+  "decision_reason": "evidence_present_but_not_verifying",
+  "evidence_ledger": [
+    "ev-b1-log"
+  ],
+  "normative_clearance": "unassessable",
+  "request_id": "demo-eps-b1",
+  "scenario_id": "evidenced-but-not-verified-claim",
+  "status": "assigned",
+  "tool": "core.epistemic_truth_state.review",
+  "trace_hash": "f9f2e153e66aaba9dcb1d7e57bb30947cb7f4dd9b09de3625b12c21b55d80b3c",
+  "trace_summary": {
+    "authority_evaluated": true,
+    "claim_fingerprint": "289e494aa06b8bd26b9cd26d61e08b966f78dcfc0f211db250ccf0ec7539a744",
+    "envelope_version": "local-v1",
+    "evidence_considered": 1,
+    "independent_support_count": 1,
+    "proposer_state_ignored": true,
+    "proposer_trace_hash_ignored": true
+  }
+}
diff --git a/demos/epistemic_truth_state/expected/inferred-from-bounded-evidence.json b/demos/epistemic_truth_state/expected/inferred-from-bounded-evidence.json
new file mode 100644
index 00000000..782fc698
--- /dev/null
+++ b/demos/epistemic_truth_state/expected/inferred-from-bounded-evidence.json
@@ -0,0 +1,33 @@
+{
+  "assigned_state": "inferred",
+  "authority_path": [
+    "demos.epistemic_truth_state.authority.validate_payload",
+    "demos.epistemic_truth_state.authority.assign_epistemic_state",
+    "demo_epistemic_truth_state_envelope(local-v1)",
+    "core.epistemic_state.coerce_epistemic_state"
+  ],
+  "decision_reason": "bounded_inference_from_evidence",
+  "evidence_ledger": [
+    "ev-c1-branch-from-main",
+    "ev-c1-tag-on-main"
+  ],
+  "inference_basis": [
+    "ev-c1-branch-from-main",
+    "ev-c1-tag-on-main"
+  ],
+  "normative_clearance": "unassessable",
+  "request_id": "demo-eps-c1",
+  "scenario_id": "inferred-from-bounded-evidence",
+  "status": "assigned",
+  "tool": "core.epistemic_truth_state.review",
+  "trace_hash": "bc11e858ece140813c2307aa9c6c602650a4cec63972f520f29ba6863f437949",
+  "trace_summary": {
+    "authority_evaluated": true,
+    "claim_fingerprint": "12e38c11f88615b1afb8e035e6e942eedd434ea0c6e3b4b25fbb7ff06695204a",
+    "envelope_version": "local-v1",
+    "evidence_considered": 2,
+    "independent_support_count": 0,
+    "proposer_state_ignored": true,
+    "proposer_trace_hash_ignored": true
+  }
+}
diff --git a/demos/epistemic_truth_state/expected/invalid-state-smuggling-attempt.json b/demos/epistemic_truth_state/expected/invalid-state-smuggling-attempt.json
new file mode 100644
index 00000000..07b916e3
--- /dev/null
+++ b/demos/epistemic_truth_state/expected/invalid-state-smuggling-attempt.json
@@ -0,0 +1,27 @@
+{
+  "assigned_state": null,
+  "authority_path": [
+    "demos.epistemic_truth_state.authority.validate_payload"
+  ],
+  "decision_reason": "invalid_payload",
+  "evidence_ledger": [],
+  "invalid_reason": "payload unexpected property 'assigned_state' (additionalProperties is false); payload unexpected property 'authority_path' (additionalProperties is false); payload unexpected property 'evidence_ledger' (additionalProperties is false); payload unexpected property 'status' (additionalProperties is false); payload unexpected property 'trace_hash' (additionalProperties is false)",
+  "normative_clearance": null,
+  "request_id": "demo-eps-f1",
+  "scenario_id": "invalid-state-smuggling-attempt",
+  "status": "invalid",
+  "tool": "core.epistemic_truth_state.review",
+  "trace_hash": "18dda5b4017b223be8eb7272eab1b8c6f1dc7a69d0326e3d1869ee95c8cf5352",
+  "trace_summary": {
+    "authority_evaluated": false,
+    "proposer_state_ignored": true,
+    "proposer_trace_hash_ignored": true,
+    "validation_errors": [
+      "payload unexpected property 'assigned_state' (additionalProperties is false)",
+      "payload unexpected property 'authority_path' (additionalProperties is false)",
+      "payload unexpected property 'evidence_ledger' (additionalProperties is false)",
+      "payload unexpected property 'status' (additionalProperties is false)",
+      "payload unexpected property 'trace_hash' (additionalProperties is false)"
+    ]
+  }
+}
diff --git a/demos/epistemic_truth_state/expected/refused-outside-scope.json b/demos/epistemic_truth_state/expected/refused-outside-scope.json
new file mode 100644
index 00000000..aa5ec03c
--- /dev/null
+++ b/demos/epistemic_truth_state/expected/refused-outside-scope.json
@@ -0,0 +1,26 @@
+{
+  "assigned_state": "scope_boundary",
+  "authority_path": [
+    "demos.epistemic_truth_state.authority.validate_payload",
+    "demos.epistemic_truth_state.authority.assign_epistemic_state",
+    "demo_epistemic_truth_state_envelope(local-v1)"
+  ],
+  "decision_reason": "outside_epistemic_envelope",
+  "evidence_ledger": [],
+  "normative_clearance": "unassessable",
+  "refusal_reason": "outside_epistemic_envelope",
+  "request_id": "demo-eps-e1",
+  "scenario_id": "refused-outside-scope",
+  "status": "refused",
+  "tool": "core.epistemic_truth_state.review",
+  "trace_hash": "c9ef9560bcf71052f9e4f323d5f6c49dc23113dcaa6a63048cfdffafec6dd024",
+  "trace_summary": {
+    "authority_evaluated": true,
+    "claim_fingerprint": "ef9317e405906823799755113ccb216ab39dd7b055c9f9883ada6480b80ef98c",
+    "envelope_version": "local-v1",
+    "evidence_considered": 1,
+    "independent_support_count": 1,
+    "proposer_state_ignored": true,
+    "proposer_trace_hash_ignored": true
+  }
+}
diff --git a/demos/epistemic_truth_state/expected/undetermined-insufficient-evidence.json b/demos/epistemic_truth_state/expected/undetermined-insufficient-evidence.json
new file mode 100644
index 00000000..5d6654d1
--- /dev/null
+++ b/demos/epistemic_truth_state/expected/undetermined-insufficient-evidence.json
@@ -0,0 +1,27 @@
+{
+  "assigned_state": "undetermined",
+  "authority_path": [
+    "demos.epistemic_truth_state.authority.validate_payload",
+    "demos.epistemic_truth_state.authority.assign_epistemic_state",
+    "demo_epistemic_truth_state_envelope(local-v1)",
+    "core.epistemic_state.coerce_epistemic_state"
+  ],
+  "decision_reason": "insufficient_evidence",
+  "evidence_ledger": [],
+  "normative_clearance": "unassessable",
+  "question": "CORE has insufficient grounded evidence to assign a determined epistemic state to this claim. Provide supporting, refuting, or premise evidence.",
+  "request_id": "demo-eps-d1",
+  "scenario_id": "undetermined-insufficient-evidence",
+  "status": "assigned",
+  "tool": "core.epistemic_truth_state.review",
+  "trace_hash": "35b319eb0186be2d9bedf65263d5acb8f397f747e7efe1ea01960655deafc7d2",
+  "trace_summary": {
+    "authority_evaluated": true,
+    "claim_fingerprint": "dc8720472531486a19edbb82c2accd279d291afe2a797c23d2745469c4f91662",
+    "envelope_version": "local-v1",
+    "evidence_considered": 1,
+    "independent_support_count": 0,
+    "proposer_state_ignored": true,
+    "proposer_trace_hash_ignored": true
+  }
+}
diff --git a/demos/epistemic_truth_state/expected/verified-supported-claim.json b/demos/epistemic_truth_state/expected/verified-supported-claim.json
new file mode 100644
index 00000000..2279ab4b
--- /dev/null
+++ b/demos/epistemic_truth_state/expected/verified-supported-claim.json
@@ -0,0 +1,29 @@
+{
+  "assigned_state": "verified",
+  "authority_path": [
+    "demos.epistemic_truth_state.authority.validate_payload",
+    "demos.epistemic_truth_state.authority.assign_epistemic_state",
+    "demo_epistemic_truth_state_envelope(local-v1)",
+    "core.epistemic_state.coerce_epistemic_state"
+  ],
+  "decision_reason": "verified_by_matching_evidence",
+  "evidence_ledger": [
+    "ev-a1-replay",
+    "ev-a1-trace"
+  ],
+  "normative_clearance": "unassessable",
+  "request_id": "demo-eps-a1",
+  "scenario_id": "verified-supported-claim",
+  "status": "assigned",
+  "tool": "core.epistemic_truth_state.review",
+  "trace_hash": "1341c27c5906ae528ecc1f0cc4ebd3f71db68f138f6d8365fe0e93dd2d7f7097",
+  "trace_summary": {
+    "authority_evaluated": true,
+    "claim_fingerprint": "cef9198360d02ce3133c1095e776ae86a714fd1c9718aa3576616f935eccdf98",
+    "envelope_version": "local-v1",
+    "evidence_considered": 2,
+    "independent_support_count": 2,
+    "proposer_state_ignored": true,
+    "proposer_trace_hash_ignored": true
+  }
+}
diff --git a/demos/epistemic_truth_state/fixtures/evidenced-but-not-verified-claim.json b/demos/epistemic_truth_state/fixtures/evidenced-but-not-verified-claim.json
new file mode 100644
index 00000000..5676936e
--- /dev/null
+++ b/demos/epistemic_truth_state/fixtures/evidenced-but-not-verified-claim.json
@@ -0,0 +1,31 @@
+{
+  "tool": "core.epistemic_truth_state.review",
+  "expected_status": "assigned",
+  "arguments": {
+    "request_id": "demo-eps-b1",
+    "scenario_id": "evidenced-but-not-verified-claim",
+    "proposer": {
+      "lane": "frontier_fixture",
+      "model_family": "model_style_proposer",
+      "proposal_id": "proposal-b1",
+      "proposed_state": "verified",
+      "trace_hash": "bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb"
+    },
+    "claim": {
+      "text": "The smoke suite passed on the current branch.",
+      "domain": "demo.local_factual",
+      "subject": "smoke_suite",
+      "predicate": "passed_on_current_branch"
+    },
+    "evidence": [
+      {
+        "evidence_id": "ev-b1-log",
+        "subject": "smoke_suite",
+        "predicate": "passed_on_current_branch",
+        "supports": true,
+        "independent": true,
+        "source_kind": "observation"
+      }
+    ]
+  }
+}
diff --git a/demos/epistemic_truth_state/fixtures/inferred-from-bounded-evidence.json b/demos/epistemic_truth_state/fixtures/inferred-from-bounded-evidence.json
new file mode 100644
index 00000000..e5be2f22
--- /dev/null
+++ b/demos/epistemic_truth_state/fixtures/inferred-from-bounded-evidence.json
@@ -0,0 +1,43 @@
+{
+  "tool": "core.epistemic_truth_state.review",
+  "expected_status": "assigned",
+  "arguments": {
+    "request_id": "demo-eps-c1",
+    "scenario_id": "inferred-from-bounded-evidence",
+    "proposer": {
+      "lane": "frontier_fixture",
+      "model_family": "model_style_proposer",
+      "proposal_id": "proposal-c1",
+      "proposed_state": "verified",
+      "trace_hash": "cccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccc"
+    },
+    "claim": {
+      "text": "The release tag is reachable from the current branch.",
+      "domain": "demo.local_factual",
+      "subject": "release_tag",
+      "predicate": "reachable_from_current_branch"
+    },
+    "evidence": [
+      {
+        "evidence_id": "ev-c1-tag-on-main",
+        "subject": "release_tag",
+        "predicate": "points_at_main",
+        "supports": true,
+        "independent": true,
+        "source_kind": "premise"
+      },
+      {
+        "evidence_id": "ev-c1-branch-from-main",
+        "subject": "current_branch",
+        "predicate": "branched_from_main",
+        "supports": true,
+        "independent": true,
+        "source_kind": "premise"
+      }
+    ],
+    "inference": {
+      "mode": "bounded_deductive",
+      "premise_ids": ["ev-c1-tag-on-main", "ev-c1-branch-from-main"]
+    }
+  }
+}
diff --git a/demos/epistemic_truth_state/fixtures/invalid-state-smuggling-attempt.json b/demos/epistemic_truth_state/fixtures/invalid-state-smuggling-attempt.json
new file mode 100644
index 00000000..2f22706a
--- /dev/null
+++ b/demos/epistemic_truth_state/fixtures/invalid-state-smuggling-attempt.json
@@ -0,0 +1,27 @@
+{
+  "tool": "core.epistemic_truth_state.review",
+  "expected_status": "invalid",
+  "arguments": {
+    "request_id": "demo-eps-f1",
+    "scenario_id": "invalid-state-smuggling-attempt",
+    "proposer": {
+      "lane": "frontier_fixture",
+      "model_family": "model_style_proposer",
+      "proposal_id": "proposal-f1",
+      "proposed_state": "verified",
+      "trace_hash": "ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff"
+    },
+    "claim": {
+      "text": "This claim ships its own verdict.",
+      "domain": "demo.local_factual",
+      "subject": "self_asserting_claim",
+      "predicate": "ships_its_own_verdict"
+    },
+    "evidence": [],
+    "assigned_state": "verified",
+    "status": "assigned",
+    "evidence_ledger": ["forged-ledger-entry"],
+    "authority_path": ["proposer.self.authority"],
+    "trace_hash": "0000000000000000000000000000000000000000000000000000000000000000"
+  }
+}
diff --git a/demos/epistemic_truth_state/fixtures/refused-outside-scope.json b/demos/epistemic_truth_state/fixtures/refused-outside-scope.json
new file mode 100644
index 00000000..e2985a0c
--- /dev/null
+++ b/demos/epistemic_truth_state/fixtures/refused-outside-scope.json
@@ -0,0 +1,31 @@
+{
+  "tool": "core.epistemic_truth_state.review",
+  "expected_status": "refused",
+  "arguments": {
+    "request_id": "demo-eps-e1",
+    "scenario_id": "refused-outside-scope",
+    "proposer": {
+      "lane": "frontier_fixture",
+      "model_family": "model_style_proposer",
+      "proposal_id": "proposal-e1",
+      "proposed_state": "verified",
+      "trace_hash": "eeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee"
+    },
+    "claim": {
+      "text": "A named public stock will close higher tomorrow.",
+      "domain": "external.realtime_market_forecast",
+      "subject": "named_public_stock",
+      "predicate": "closes_higher_tomorrow"
+    },
+    "evidence": [
+      {
+        "evidence_id": "ev-e1-rumor",
+        "subject": "named_public_stock",
+        "predicate": "closes_higher_tomorrow",
+        "supports": true,
+        "independent": true,
+        "source_kind": "observation"
+      }
+    ]
+  }
+}
diff --git a/demos/epistemic_truth_state/fixtures/undetermined-insufficient-evidence.json b/demos/epistemic_truth_state/fixtures/undetermined-insufficient-evidence.json
new file mode 100644
index 00000000..788ac61b
--- /dev/null
+++ b/demos/epistemic_truth_state/fixtures/undetermined-insufficient-evidence.json
@@ -0,0 +1,31 @@
+{
+  "tool": "core.epistemic_truth_state.review",
+  "expected_status": "assigned",
+  "arguments": {
+    "request_id": "demo-eps-d1",
+    "scenario_id": "undetermined-insufficient-evidence",
+    "proposer": {
+      "lane": "frontier_fixture",
+      "model_family": "model_style_proposer",
+      "proposal_id": "proposal-d1",
+      "proposed_state": "verified",
+      "trace_hash": "dddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddd"
+    },
+    "claim": {
+      "text": "The nightly benchmark improved over last week.",
+      "domain": "demo.local_factual",
+      "subject": "nightly_benchmark",
+      "predicate": "improved_over_last_week"
+    },
+    "evidence": [
+      {
+        "evidence_id": "ev-d1-unrelated",
+        "subject": "documentation_pass",
+        "predicate": "merged_to_main",
+        "supports": true,
+        "independent": true,
+        "source_kind": "observation"
+      }
+    ]
+  }
+}
diff --git a/demos/epistemic_truth_state/fixtures/verified-supported-claim.json b/demos/epistemic_truth_state/fixtures/verified-supported-claim.json
new file mode 100644
index 00000000..ea8b9893
--- /dev/null
+++ b/demos/epistemic_truth_state/fixtures/verified-supported-claim.json
@@ -0,0 +1,39 @@
+{
+  "tool": "core.epistemic_truth_state.review",
+  "expected_status": "assigned",
+  "arguments": {
+    "request_id": "demo-eps-a1",
+    "scenario_id": "verified-supported-claim",
+    "proposer": {
+      "lane": "frontier_fixture",
+      "model_family": "model_style_proposer",
+      "proposal_id": "proposal-a1",
+      "proposed_state": "verified",
+      "trace_hash": "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa"
+    },
+    "claim": {
+      "text": "The reviewed teaching loop ran on the pinned cognition pack.",
+      "domain": "demo.local_factual",
+      "subject": "reviewed_teaching_loop",
+      "predicate": "ran_on_pinned_cognition_pack"
+    },
+    "evidence": [
+      {
+        "evidence_id": "ev-a1-trace",
+        "subject": "reviewed_teaching_loop",
+        "predicate": "ran_on_pinned_cognition_pack",
+        "supports": true,
+        "independent": true,
+        "source_kind": "vault"
+      },
+      {
+        "evidence_id": "ev-a1-replay",
+        "subject": "reviewed_teaching_loop",
+        "predicate": "ran_on_pinned_cognition_pack",
+        "supports": true,
+        "independent": true,
+        "source_kind": "teaching"
+      }
+    ]
+  }
+}
diff --git a/demos/epistemic_truth_state/run_demo.py b/demos/epistemic_truth_state/run_demo.py
new file mode 100644
index 00000000..6c6b9f45
--- /dev/null
+++ b/demos/epistemic_truth_state/run_demo.py
@@ -0,0 +1,179 @@
+"""Run the model-proposer-to-CORE epistemic truth-state authority demo.
+
+Each fixture is evaluated twice.  The run fails if any scenario drifts from its
+committed expected artifact or if the two executions differ byte-for-byte.
+"""
+
+from __future__ import annotations
+
+import argparse
+import json
+import shutil
+import sys
+import tempfile
+from pathlib import Path
+from typing import Any
+
+REPO_ROOT = Path(__file__).resolve().parents[2]
+sys.path.insert(0, str(REPO_ROOT))
+
+from demos.epistemic_truth_state.authority import TOOL_NAME, load_schema, run_authority  # noqa: E402
+
+_HERE = Path(__file__).resolve().parent
+FIXTURES_DIR = _HERE / "fixtures"
+EXPECTED_DIR = _HERE / "expected"
+DEFAULT_OUT_DIR = _HERE / "out"
+_TMP_ROOT = Path(tempfile.gettempdir()).resolve()
+
+
+def _render(payload: dict[str, Any]) -> str:
+    return json.dumps(payload, sort_keys=True, indent=2) + "\n"
+
+
+def fixture_paths() -> list[Path]:
+    return sorted(FIXTURES_DIR.glob("*.json"))
+
+
+def expected_path(scenario_id: str) -> Path:
+    return EXPECTED_DIR / f"{scenario_id}.json"
+
+
+def run_fixture(path: Path) -> dict[str, Any]:
+    fixture = json.loads(path.read_text(encoding="utf-8"))
+    if fixture["tool"] != TOOL_NAME:
+        raise ValueError(f"{path.name} names {fixture['tool']!r}; expected {TOOL_NAME!r}")
+    run_a = run_authority(fixture["arguments"])
+    run_b = run_authority(fixture["arguments"])
+    if _render(run_a) != _render(run_b):
+        raise AssertionError(f"{path.name} is not deterministic across double-run execution")
+    return run_a
+
+
+def _is_relative_to(path: Path, root: Path) -> bool:
+    try:
+        path.relative_to(root)
+        return True
+    except ValueError:
+        return False
+
+
+def _custom_out_allowed(out_dir: Path) -> bool:
+    resolved = out_dir.resolve()
+    if resolved in {
+        Path("/"),
+        REPO_ROOT.resolve(),
+        _HERE.resolve(),
+        _HERE.parent.resolve(),
+        Path.home().resolve(),
+        Path.cwd().resolve(),
+    }:
+        return False
+    return _is_relative_to(resolved, _HERE.resolve()) or _is_relative_to(resolved, _TMP_ROOT)
+
+
+def _clearable_out_dir(out_dir: Path) -> tuple[bool, str | None]:
+    resolved = out_dir.resolve()
+    default_resolved = DEFAULT_OUT_DIR.resolve()
+    if resolved == default_resolved:
+        return True, None
+    if not _custom_out_allowed(out_dir):
+        return False, (
+            f"refusing to clear {out_dir}: custom out dir must resolve under "
+            f"{_HERE} or {_TMP_ROOT}"
+        )
+    if not (out_dir / "summary.json").exists():
+        return False, (
+            f"refusing to clear {out_dir}: custom out dir requires demo summary.json marker"
+        )
+    return True, None
+
+
+def main() -> int:
+    parser = argparse.ArgumentParser(description=__doc__)
+    parser.add_argument("--out", type=Path, default=DEFAULT_OUT_DIR)
+    parser.add_argument("--allow-custom-out", action="store_true")
+    parser.add_argument("--json", action="store_true")
+    parser.add_argument("--update-expected", action="store_true")
+    args = parser.parse_args()
+
+    out_dir = args.out
+    if out_dir.resolve() != DEFAULT_OUT_DIR.resolve() and args.allow_custom_out:
+        print(
+            "--allow-custom-out is deprecated; this demo now enforces the output-root policy directly",
+            file=sys.stderr,
+        )
+    if out_dir.exists():
+        allowed, reason = _clearable_out_dir(out_dir)
+        if not allowed:
+            assert reason is not None
+            print(reason, file=sys.stderr)
+            return 2
+        shutil.rmtree(out_dir)
+    out_dir.mkdir(parents=True)
+
+    schema_doc = load_schema()
+    results: list[dict[str, Any]] = []
+    all_passed = True
+
+    for fixture_path in fixture_paths():
+        fixture = json.loads(fixture_path.read_text(encoding="utf-8"))
+        scenario_id = fixture["arguments"]["scenario_id"]
+        scenario_dir = out_dir / scenario_id
+        scenario_dir.mkdir(parents=True, exist_ok=True)
+        response = run_fixture(fixture_path)
+        artifact = _render(response)
+        (scenario_dir / "response.json").write_text(artifact, encoding="utf-8")
+
+        problems: list[str] = []
+        if response["status"] != fixture["expected_status"]:
+            problems.append(
+                f"status {response['status']!r} != expected {fixture['expected_status']!r}"
+            )
+        ref = expected_path(scenario_id)
+        if args.update_expected:
+            EXPECTED_DIR.mkdir(exist_ok=True)
+            ref.write_text(artifact, encoding="utf-8")
+        elif not ref.exists():
+            problems.append("missing committed expected artifact")
+        elif ref.read_text(encoding="utf-8") != artifact:
+            problems.append("response drifted from committed expected artifact")
+
+        all_passed &= not problems
+        results.append(
+            {
+                "scenario_id": scenario_id,
+                "status": response["status"],
+                "assigned_state": response["assigned_state"],
+                "decision_reason": response["decision_reason"],
+                "trace_hash": response["trace_hash"],
+                "passed": not problems,
+                "problems": problems,
+            }
+        )
+
+    summary = {
+        "tool": schema_doc["name"],
+        "all_passed": all_passed,
+        "scenarios": results,
+        "updated_expected": bool(args.update_expected),
+    }
+    summary_text = _render(summary)
+    (out_dir / "summary.json").write_text(summary_text, encoding="utf-8")
+    if args.json:
+        print(summary_text, end="")
+    else:
+        for row in results:
+            mark = "PASS" if row["passed"] else "FAIL"
+            print(
+                f"[{mark}] {row['scenario_id']}: {row['status']}"
+                f" / {row['assigned_state']} ({row['decision_reason']})"
+            )
+            print(f"       trace_hash: {row['trace_hash'][:16]}…")
+            for problem in row["problems"]:
+                print(f"       x {problem}")
+        print(f"{sum(r['passed'] for r in results)}/{len(results)} scenarios passed")
+    return 0 if all_passed else 1
+
+
+if __name__ == "__main__":
+    raise SystemExit(main())
diff --git a/demos/epistemic_truth_state/schema.json b/demos/epistemic_truth_state/schema.json
new file mode 100644
index 00000000..d98a9995
--- /dev/null
+++ b/demos/epistemic_truth_state/schema.json
@@ -0,0 +1,192 @@
+{
+  "name": "core.epistemic_truth_state.review",
+  "title": "CORE epistemic truth-state authority demo",
+  "description": "Submit one model-style claim proposal to CORE's local deterministic epistemic-state authority. CORE validates a closed payload, ignores any proposer-supplied proposed_state and trace hash, assigns a typed epistemic state drawn from the canonical core.epistemic_state taxonomy, derives normative clearance, builds an evidence ledger, and returns assigned | refused | invalid plus a deterministic trace artifact. The proposer cannot set the assigned state, status, clearance, evidence ledger, authority path, or trace hash.",
+  "inputSchema": {
+    "type": "object",
+    "properties": {
+      "request_id": {
+        "type": "string",
+        "pattern": "^[A-Za-z0-9._-]{1,64}$"
+      },
+      "scenario_id": {
+        "type": "string",
+        "pattern": "^[a-z0-9._-]{1,64}$"
+      },
+      "proposer": {
+        "type": "object",
+        "properties": {
+          "lane": {
+            "type": "string",
+            "enum": ["frontier_fixture", "local_fixture"]
+          },
+          "model_family": {
+            "type": "string",
+            "enum": ["model_style_proposer"]
+          },
+          "proposal_id": {
+            "type": "string",
+            "pattern": "^[A-Za-z0-9._-]{1,64}$"
+          },
+          "proposed_state": {
+            "type": "string",
+            "minLength": 1,
+            "maxLength": 64
+          },
+          "trace_hash": {
+            "type": "string",
+            "pattern": "^[a-f0-9]{64}$"
+          }
+        },
+        "required": ["lane", "model_family", "proposal_id"],
+        "additionalProperties": false
+      },
+      "claim": {
+        "type": "object",
+        "properties": {
+          "text": {
+            "type": "string",
+            "minLength": 1,
+            "maxLength": 500
+          },
+          "domain": {
+            "type": "string",
+            "pattern": "^[a-z0-9._-]{1,64}$"
+          },
+          "subject": {
+            "type": "string",
+            "minLength": 1,
+            "maxLength": 120
+          },
+          "predicate": {
+            "type": "string",
+            "minLength": 1,
+            "maxLength": 120
+          }
+        },
+        "required": ["text", "domain", "subject", "predicate"],
+        "additionalProperties": false
+      },
+      "evidence": {
+        "type": "array",
+        "items": {
+          "type": "object",
+          "properties": {
+            "evidence_id": {
+              "type": "string",
+              "pattern": "^[A-Za-z0-9._-]{1,64}$"
+            },
+            "subject": {
+              "type": "string",
+              "minLength": 1,
+              "maxLength": 120
+            },
+            "predicate": {
+              "type": "string",
+              "minLength": 1,
+              "maxLength": 120
+            },
+            "supports": {
+              "type": "boolean"
+            },
+            "independent": {
+              "type": "boolean"
+            },
+            "source_kind": {
+              "type": "string",
+              "enum": ["pack", "teaching", "vault", "observation", "premise"]
+            }
+          },
+          "required": ["evidence_id", "subject", "predicate", "supports"],
+          "additionalProperties": false
+        }
+      },
+      "inference": {
+        "type": "object",
+        "properties": {
+          "mode": {
+            "type": "string",
+            "enum": ["bounded_deductive", "bounded_arithmetic"]
+          },
+          "premise_ids": {
+            "type": "array",
+            "items": {
+              "type": "string",
+              "pattern": "^[A-Za-z0-9._-]{1,64}$"
+            }
+          }
+        },
+        "required": ["premise_ids"],
+        "additionalProperties": false
+      }
+    },
+    "required": ["request_id", "scenario_id", "proposer", "claim"],
+    "additionalProperties": false
+  },
+  "outputSchema": {
+    "type": "object",
+    "properties": {
+      "status": {
+        "type": "string",
+        "enum": ["assigned", "refused", "invalid"]
+      },
+      "request_id": {
+        "type": ["string", "null"]
+      },
+      "scenario_id": {
+        "type": ["string", "null"]
+      },
+      "authority_path": {
+        "type": "array",
+        "items": {
+          "type": "string"
+        }
+      },
+      "decision_reason": {
+        "type": "string"
+      },
+      "assigned_state": {
+        "type": ["string", "null"]
+      },
+      "normative_clearance": {
+        "type": ["string", "null"]
+      },
+      "evidence_ledger": {
+        "type": "array",
+        "items": {
+          "type": "string"
+        }
+      },
+      "trace_hash": {
+        "type": "string"
+      },
+      "trace_summary": {
+        "type": "object"
+      },
+      "inference_basis": {
+        "type": ["array", "null"]
+      },
+      "question": {
+        "type": ["string", "null"]
+      },
+      "refusal_reason": {
+        "type": ["string", "null"]
+      },
+      "invalid_reason": {
+        "type": ["string", "null"]
+      }
+    },
+    "required": [
+      "status",
+      "request_id",
+      "scenario_id",
+      "authority_path",
+      "decision_reason",
+      "assigned_state",
+      "normative_clearance",
+      "evidence_ledger",
+      "trace_hash",
+      "trace_summary"
+    ]
+  }
+}
diff --git a/tests/test_epistemic_truth_state_demo.py b/tests/test_epistemic_truth_state_demo.py
new file mode 100644
index 00000000..101770a7
--- /dev/null
+++ b/tests/test_epistemic_truth_state_demo.py
@@ -0,0 +1,283 @@
+from __future__ import annotations
+
+import ast
+import copy
+import json
+from pathlib import Path
+
+import pytest
+
+from core.epistemic_state import EpistemicState, NormativeClearance
+from demos.epistemic_truth_state import authority
+from demos.epistemic_truth_state import run_demo as demo_runner
+
+DEMO_DIR = Path(authority.__file__).resolve().parent
+FIXTURES_DIR = DEMO_DIR / "fixtures"
+EXPECTED_DIR = DEMO_DIR / "expected"
+
+SCENARIOS = {
+    "verified-supported-claim": ("assigned", "verified"),
+    "evidenced-but-not-verified-claim": ("assigned", "evidenced"),
+    "inferred-from-bounded-evidence": ("assigned", "inferred"),
+    "undetermined-insufficient-evidence": ("assigned", "undetermined"),
+    "refused-outside-scope": ("refused", "scope_boundary"),
+    "invalid-state-smuggling-attempt": ("invalid", None),
+}
+
+
+def _fixture(name: str) -> dict[str, object]:
+    return json.loads((FIXTURES_DIR / name).read_text(encoding="utf-8"))
+
+
+def _arguments(name: str) -> dict[str, object]:
+    return _fixture(f"{name}.json")["arguments"]
+
+
+def _run(name: str) -> dict[str, object]:
+    return authority.run_authority(_arguments(name))
+
+
+def test_schema_is_closed_recursively():
+    schema = authority.load_schema()["inputSchema"]
+    assert schema["type"] == "object"
+    assert schema["additionalProperties"] is False
+    assert schema["properties"]["proposer"]["additionalProperties"] is False
+    assert schema["properties"]["claim"]["additionalProperties"] is False
+    assert schema["properties"]["evidence"]["items"]["additionalProperties"] is False
+    assert schema["properties"]["inference"]["additionalProperties"] is False
+
+    # Every nested object in the input schema is closed, recursively.
+    def _assert_closed(spec: dict[str, object], path: str) -> None:
+        node_type = spec.get("type")
+        if node_type == "object":
+            assert spec.get("additionalProperties") is False, f"{path} is not closed"
+            for name, child in spec.get("properties", {}).items():
+                _assert_closed(child, f"{path}.{name}")
+        elif node_type == "array":
+            _assert_closed(spec["items"], f"{path}[]")
+
+    _assert_closed(schema, "inputSchema")
+
+
+def test_all_scenarios_work():
+    for name, (status, assigned_state) in SCENARIOS.items():
+        response = _run(name)
+        assert response["status"] == status, name
+        assert response["assigned_state"] == assigned_state, name
+
+
+def test_uses_canonical_epistemic_state_enum():
+    # authority.py imports the canonical taxonomy and defines no parallel enum.
+    tree = ast.parse((DEMO_DIR / "authority.py").read_text(encoding="utf-8"))
+    imported_from_core = False
+    for node in ast.walk(tree):
+        if isinstance(node, ast.ClassDef):
+            base_names = {
+                base.id for base in node.bases if isinstance(base, ast.Name)
+            } | {
+                base.attr for base in node.bases if isinstance(base, ast.Attribute)
+            }
+            assert "Enum" not in base_names, "demo must not define a parallel enum"
+        if isinstance(node, ast.ImportFrom) and node.module == "core.epistemic_state":
+            names = {alias.name for alias in node.names}
+            assert {"EpistemicState", "coerce_epistemic_state"} <= names
+            imported_from_core = True
+    assert imported_from_core
+
+    # Every emitted state/clearance is a member of the canonical enums.
+    valid_states = {state.value for state in EpistemicState}
+    valid_clearances = {clearance.value for clearance in NormativeClearance}
+    for name in SCENARIOS:
+        artifact = json.loads((EXPECTED_DIR / f"{name}.json").read_text(encoding="utf-8"))
+        if artifact["assigned_state"] is not None:
+            assert artifact["assigned_state"] in valid_states, name
+        if artifact["normative_clearance"] is not None:
+            assert artifact["normative_clearance"] in valid_clearances, name
+
+
+def test_verified_requires_matching_evidence():
+    response = _run("verified-supported-claim")
+    assert response["assigned_state"] == "verified"
+    # This demo runs no normative/safety/ethics clearance pass, so even a
+    # verified claim stays UNASSESSABLE rather than positively cleared.
+    assert response["normative_clearance"] == "unassessable"
+    assert response["evidence_ledger"] == ["ev-a1-replay", "ev-a1-trace"]
+
+    # Drop one independent record: a single supporting record cannot verify.
+    one_record = _arguments("verified-supported-claim")
+    one_record["evidence"] = one_record["evidence"][:1]
+    downgraded = authority.run_authority(one_record)
+    assert downgraded["assigned_state"] == "evidenced"
+    assert downgraded["decision_reason"] == "evidence_present_but_not_verifying"
+
+    # Subject/predicate mismatch is not matching evidence at all.
+    mismatched = _arguments("verified-supported-claim")
+    for record in mismatched["evidence"]:
+        record["predicate"] = "something_else"
+    none_match = authority.run_authority(mismatched)
+    assert none_match["assigned_state"] == "undetermined"
+    assert none_match["decision_reason"] == "insufficient_evidence"
+
+
+def test_clearance_is_unassessable_for_all_non_invalid_outputs():
+    # The demo assigns epistemic truth-state only; it runs no normative/safety/
+    # ethics clearance pass, so it must never positively clear anything.
+    for name in SCENARIOS:
+        response = _run(name)
+        if response["status"] == "invalid":
+            assert response["normative_clearance"] is None, name
+        else:
+            assert response["normative_clearance"] == "unassessable", name
+
+
+def test_evidenced_state_for_single_support():
+    response = _run("evidenced-but-not-verified-claim")
+    assert response["status"] == "assigned"
+    assert response["assigned_state"] == "evidenced"
+    assert response["decision_reason"] == "evidence_present_but_not_verifying"
+    assert response["evidence_ledger"] == ["ev-b1-log"]
+
+
+def test_inferred_includes_inference_basis():
+    response = _run("inferred-from-bounded-evidence")
+    assert response["assigned_state"] == "inferred"
+    assert response["decision_reason"] == "bounded_inference_from_evidence"
+    assert response["inference_basis"] == ["ev-c1-branch-from-main", "ev-c1-tag-on-main"]
+    assert response["evidence_ledger"] == response["inference_basis"]
+
+
+def test_inference_with_unresolved_premise_does_not_infer():
+    payload = _arguments("inferred-from-bounded-evidence")
+    payload["inference"]["premise_ids"] = ["ev-c1-tag-on-main", "does-not-exist"]
+    response = authority.run_authority(payload)
+    assert response["assigned_state"] == "undetermined"
+
+
+def test_undetermined_emits_question():
+    response = _run("undetermined-insufficient-evidence")
+    assert response["assigned_state"] == "undetermined"
+    assert response["evidence_ledger"] == []
+    assert "insufficient grounded evidence" in response["question"]
+
+
+def test_scope_boundary_refuses():
+    response = _run("refused-outside-scope")
+    assert response["status"] == "refused"
+    assert response["assigned_state"] == "scope_boundary"
+    assert response["refusal_reason"] == "outside_epistemic_envelope"
+    assert response["decision_reason"] == "outside_epistemic_envelope"
+    assert response["evidence_ledger"] == []
+
+
+def test_proposer_cannot_set_assigned_state():
+    payload = _arguments("verified-supported-claim")
+    payload["assigned_state"] = "verified"
+    response = authority.run_authority(payload)
+    assert response["status"] == "invalid"
+    assert "payload unexpected property 'assigned_state'" in response["invalid_reason"]
+
+
+def test_proposer_cannot_smuggle_root_authority_fields():
+    response = _run("invalid-state-smuggling-attempt")
+    assert response["status"] == "invalid"
+    assert response["assigned_state"] is None
+    assert response["normative_clearance"] is None
+    for forged in ("assigned_state", "status", "evidence_ledger", "authority_path", "trace_hash"):
+        assert f"unexpected property '{forged}'" in response["invalid_reason"]
+
+
+def test_proposer_trace_hash_is_ignored():
+    payload = _arguments("verified-supported-claim")
+    response = authority.run_authority(payload)
+    assert response["trace_summary"]["proposer_trace_hash_ignored"] is True
+    assert response["trace_hash"] != payload["proposer"]["trace_hash"]
+
+
+def test_proposer_proposed_state_is_ignored():
+    # Proposer claims "verified" but supplies zero evidence: CORE assigns undetermined.
+    payload = _arguments("undetermined-insufficient-evidence")
+    payload["proposer"]["proposed_state"] = "verified"
+    payload["evidence"] = []
+    response = authority.run_authority(payload)
+    assert response["trace_summary"]["proposer_state_ignored"] is True
+    assert response["assigned_state"] == "undetermined"
+
+
+def test_invalid_payload_fails_before_state_evaluation(monkeypatch):
+    def _explode(_payload: dict[str, object]) -> dict[str, object]:
+        raise AssertionError("state evaluation ran for an invalid payload")
+
+    monkeypatch.setattr(authority, "assign_epistemic_state", _explode)
+    response = _run("invalid-state-smuggling-attempt")
+    assert response["status"] == "invalid"
+    assert response["trace_summary"]["authority_evaluated"] is False
+
+
+def test_double_run_outputs_byte_identical():
+    for name in SCENARIOS:
+        payload = _arguments(name)
+        run_a = authority.run_authority(payload)
+        run_b = authority.run_authority(payload)
+        rendered_a = json.dumps(run_a, sort_keys=True, indent=2)
+        rendered_b = json.dumps(run_b, sort_keys=True, indent=2)
+        assert rendered_a == rendered_b, name
+
+
+def test_expected_artifact_tampering_fails(tmp_path):
+    scenario_id = "verified-supported-claim"
+    ref = EXPECTED_DIR / f"{scenario_id}.json"
+    original = ref.read_text(encoding="utf-8")
+    try:
+        ref.write_text(original.replace("verified", "evidenced", 1), encoding="utf-8")
+        with pytest.MonkeyPatch.context() as patch:
+            patch.setattr("sys.argv", ["run_demo.py", "--out", str(tmp_path / "out")])
+            assert demo_runner.main() == 1
+    finally:
+        ref.write_text(original, encoding="utf-8")
+
+
+def test_run_demo_all_passes_against_expected(tmp_path, monkeypatch):
+    out_dir = tmp_path / "demo-out"
+    monkeypatch.setattr("sys.argv", ["run_demo.py", "--out", str(out_dir)])
+    assert demo_runner.main() == 0
+
+
+def test_run_demo_default_out_still_works(monkeypatch):
+    monkeypatch.setattr("sys.argv", ["run_demo.py"])
+    assert demo_runner.main() == 0
+
+
+def test_run_demo_refuses_non_default_dir_without_marker(tmp_path, monkeypatch):
+    out_dir = tmp_path / "missing-marker"
+    out_dir.mkdir()
+    monkeypatch.setattr("sys.argv", ["run_demo.py", "--out", str(out_dir)])
+    assert demo_runner.main() == 2
+
+
+@pytest.mark.parametrize("target", [".", ".."])
+def test_run_demo_refuses_parent_like_paths(target: str, monkeypatch):
+    monkeypatch.setattr("sys.argv", ["run_demo.py", "--out", target])
+    assert demo_runner.main() == 2
+
+
+def test_no_network_subprocess_eval_or_exec_imports_or_calls():
+    forbidden_imports = {"subprocess", "socket", "requests", "httpx", "urllib", "urllib.request"}
+    forbidden_calls = {"eval", "exec", "compile", "open_connection", "create_connection", "Popen", "run"}
+    scanned = [
+        DEMO_DIR / "__init__.py",
+        DEMO_DIR / "authority.py",
+        DEMO_DIR / "run_demo.py",
+    ]
+    for path in scanned:
+        tree = ast.parse(path.read_text(encoding="utf-8"))
+        for node in ast.walk(tree):
+            if isinstance(node, ast.Import):
+                for alias in node.names:
+                    assert alias.name not in forbidden_imports
+            elif isinstance(node, ast.ImportFrom):
+                assert (node.module or "") not in forbidden_imports
+            elif isinstance(node, ast.Call):
+                if isinstance(node.func, ast.Name):
+                    assert node.func.id not in forbidden_calls
+                elif isinstance(node.func, ast.Attribute):
+                    assert node.func.attr not in forbidden_calls