Now, what is the difference between the two? How does one determine whether a law is just or unjust? A just law is a man made code that squares with the moral law or the law of God. An unjust law is a code that is out of harmony with the moral law.
...Thus it is that I can urge men to obey the 1954 decision of the Supreme Court, for it is morally right; and I can urge them to disobey segregation ordinances, for they are morally wrong. ...A law is unjust if it is inflicted on a minority that, as a result of being denied the right to vote, had no part in enacting or devising the law.
I hope you are able to see the distinction I am trying to point out. In no sense do I advocate evading or defying the law, as would the rabid segregationist. That would lead to anarchy. One who breaks an unjust law must do so openly, lovingly, and with a willingness to accept the penalty. I submit that an individual who breaks a law that conscience tells him is unjust, and who willingly accepts the penalty of imprisonment in order to arouse the conscience of the community over its injustice, is in reality expressing the highest respect for law. Of course, there is nothing new about this kind of civil disobedience. It was evidenced sublimely in the refusal of Shadrach, Meshach and Abednego to obey the laws of Nebuchadnezzar, on the ground that a higher moral law was at stake. It was practiced superbly by the early Christians, who were willing to face hungry lions and the excruciating pain of chopping blocks rather than submit to certain unjust laws of the Roman Empire. To a degree, academic freedom is a reality today because Socrates practiced civil disobedience. In our own nation, the Boston Tea Party represented a massive act of civil disobedience.
We should never forget that everything Adolf Hitler did in Germany was 'legal' and everything the Hungarian freedom fighters did in Hungary was 'illegal.' It was 'illegal' to aid and comfort a Jew in Hitler's Germany. Even so, I am sure that, had I lived in Germany at the time, I would have aided and comforted my Jewish brothers. If today I lived in a Communist country where certain principles dear to the Christian faith are suppressed, I would openly advocate disobeying that country's antireligious laws."
-- Dr. Martin Luther King, Jr., Letter from a Birmingham Jail