Illegal versus unlawful

I posed the question to Google AI and this is what it had to say

While "unlawful" and "illegal" are often used interchangeably,

illegal specifically means a violation of a written law, while unlawful is a broader term for anything that is not authorized by law, which could be a violation of a specific statute or simply against public policy. Essentially, all illegal acts are unlawful, but not all unlawful acts are necessarily illegal in the criminal sense. 

Illegal

• Definition: An act that is expressly forbidden by a specific statute or law.

• Connotation: Often used for actions that have a clear and defined criminal or civil penalty.

• Example: Theft is illegal because it is a direct violation of criminal law. 

Unlawful

• Definition: An act that is not permitted or authorized by law, but might not be a direct violation of a specific statute.

• Connotation: Can be a more general term for any conduct that contravenes a legal standard or public policy.

• Examples:

  • A business agreement that is against public policy (e.g., an agreement to stifle trade) is unlawful, even if no specific law is broken by the wording itself.

  • An order given to a service member that violates the Constitution or international human rights law is unlawful, even if it is not a "crime" in the traditional sense.