Any law the promotes liberty, equality and justice is a just law. A unjust law benefits some of the people at the expense of others. Just laws punish those who violate the rights of others while unjust laws reward the rich and powerful few at the expense of the many.
Just laws promote peace, prosperity and freedom and unjust laws lead to perpetual wars, debt and human bondage.
It is the responsibility of every just man and woman to comply with laws that are just and a duty to refuse to obey those that are not. When an unjust law is enforced, the government promotes the tyranny it is supposed to prevent.