Key legal question
Whether the appellant could rely on an unavoidable error of law under Art. 21 CP
Extracted holding
The appellant could not invoke Art. 21 CP because he was found to have known, or at least suspected, the unlawfulness of employing persons without work authorization; the error, if any, was not established.
Extracted reasoning
The cantonal findings were not arbitrary. Indications such as his long residence in Switzerland, experience as an employer, administrative familiarity, inquiries about residence permits, and the accountant's letter supported awareness or at least acceptance of illegality.