diff --git a/packages/agent-compliance/schemas/__init__.py b/packages/agent-compliance/schemas/__init__.py
new file mode 100644
index 00000000..648154f2
--- /dev/null
+++ b/packages/agent-compliance/schemas/__init__.py
@@ -0,0 +1,4 @@
+"""Governance policy schemas for validation."""
+from agent_compliance.schemas.policy_schema import PolicySchema, validate_policy
+
+__all__ = ["PolicySchema", "validate_policy"]
diff --git a/packages/agent-compliance/schemas/policy_schema.py b/packages/agent-compliance/schemas/policy_schema.py
index 0104b1e3..cbeedec6 100644
--- a/packages/agent-compliance/schemas/policy_schema.py
+++ b/packages/agent-compliance/schemas/policy_schema.py
@@ -1,16 +1,39 @@
 from pydantic import BaseModel, Field
 from typing import List, Optional, Dict, Any
 
+
 class PolicySchema(BaseModel):
     """
     JSON Schema for governance policies.
     Addresses request for better validation (#305).
     """
+
     id: str = Field(..., description="Unique policy identifier")
     name: str = Field(..., description="Human-readable policy name")
     version: str = Field("1.0.0")
     rules: List[Dict[str, Any]] = Field(default_factory=list)
     metadata: Optional[Dict[str, Any]] = None
 
-def validate_policy(data: Dict[str, Any]):
-    return PolicySchema(**data)
+
+class PolicyValidationError(Exception):
+    """Raised when a governance policy fails schema validation."""
+
+    pass
+
+
+def validate_policy(data: Dict[str, Any]) -> PolicySchema:
+    """Validate a governance policy dict against the schema.
+
+    Args:
+        data: Policy data dictionary.
+
+    Returns:
+        Validated PolicySchema instance.
+
+    Raises:
+        PolicyValidationError: If validation fails with field-level details.
+    """
+    try:
+        return PolicySchema(**data)
+    except Exception as e:
+        raise PolicyValidationError(f"Policy validation failed: {e}") from e