| outside the workplace appropriate? The schools have not said he can not paint how ever he chooses, they have said because he choose to paint in a manner the school system believes in inappropriate they may not continue to employ him.
Many people have a "morals" clause in their employment agreements. Be accepting the position (and/or signing the document) the person agrees that the morals clause is something they are willing to adhear to or face disciplinary action (including termination). If there is no such conduct clause, and one is later imposed on the employee that would be wrong. If the clause existed in the employee's original (and subsequent) employment agreemnets I would say the employee must behave in a manner dictated by the clause or face the consequences because they were not forced to take that position.
It is not any different than a home owner agreeing to keep his property in a particular manner as dictated by covenents and home owner's association by laws they had to agree to to purchase a specific property. | 
