Unless there is a provision to the contrary in the definition of a crime, reasonable ignorance of fact or mistake of fact which precludes the presence of any mental element required in that crime is a defense to any prosecution for that crime.
La. R.S. 14:16
Mistake of fact
Known as the Louisiana Criminal Code
The act spans §§ 14-1 to 14-9 (36 sections).
Official source: Louisiana State Legislature. Reproduced from public-domain Louisiana statutes; confirm against the official source for the current text. Not legal advice.