Obligation to follow the law
From Textop Wiki
Everyone is obligated to inform himself of all written laws that concern his own future actions.
If the question be of obedience to a public officer, to have seen his commission with the public seal, and heard it read, or to have had the means to be informed of it, if a man would, is a sufficient verification of his authority. For every man is obliged to do his best endeavour to inform himself of all written laws that may concern his own future actions.
Hobbes, Lev XXVI 19