Question

In a certain city, a local ordinance was passed requiring all business establishments to secure a permit and display it prominently in their respective premises. The penalty for non-compliance is a fine and closure of the establishment.

Mr. Santos owns a small convenience store in the city, but he was not aware of this local ordinance. One day, a city inspector visits his store and notices that he does not have the required permit displayed. The inspector informs Mr. Santos of the violation and imposes the corresponding penalties.

Unaware of the law, Mr. Santos contends that he should not be held liable for the violation since he was ignorant of the local ordinance.

Is Mr. Santos' argument valid under the law? Discuss.