Decent people should not obey immoral laws. What's moral and immoral can be a contentious issue, but there are some broad guides for deciding what laws and government actions are immoral. Lysander S. Spooner, one of America's great 19th-century thinkers, said no person or group of people can "authorize government to destroy or take away from men their natural rights; for natural rights are inalienable, and can no more be surrendered to government -- which is but an association of individuals -- than to a single individual." French economist/philosopher Frederic Bastiat (1801-50) gave a test for immoral government acts: "See if the law benefits one citizen at the expense of another by doing what the citizen himself cannot do without committing a crime." He added in his book "The Law," "When law and morality contradict each other, the citizen has the cruel alternative of either losing his moral sense or losing his respect for the law."
http://townhall.com/columnists/walterewilliams/2011/08/24/legal_obedience/page/full/Williams is mirroring MLK Jr.'s writings in
Letter from a Birmingham Jail, and also St. Augustine before him, who MLK mirrored.
We have a moral obligation to disobey unjust laws.
One may well ask: "How can you advocate breaking some laws and obeying others?" The answer lies in the fact that there are two types of laws: just and unjust. I would be the first to advocate obeying just laws. One has not only a legal but a moral responsibility to obey just laws. Conversely, one has a moral responsibility to disobey unjust laws. I would agree with St. Augustine that "an unjust law is no law at all."
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. To put it in the terms of St. Thomas Aquinas: An unjust law is a human law that is not rooted in eternal law and natural law. Any law that uplifts human personality is just. Any law that degrades human personality is unjust. -MLK Jr.
http://www.africa.upenn.edu/Articles_Gen/Letter_Birmingham.htmlAlso, if you've never read,
Letter from a Birmingham Jail, it also is a great read. It can be read in its entirety at the link directly above.
Also, here is another great read, The Law by Fr?d?ric Bastiat
http://bastiat.org/en/the_law.html