I don't know if I would agree that an unjust law is no law at all, exactly, but I think an unjust law, while still being a law, is one that we should feel justified in breaking. I agree with MLK though, that we shouldn't break it in a sneaky way, just trying to get away with it, but completely obviously and out in the open, so that everybody can see that we are breaking it and hopefully understand why. To do it in secret just seems like you're trying to get away with a crime, but to do it publicly makes a statement. If a law is truly unjust then it is absolutely morally justified to disobey that law.
I think there are sometimes other avenues you should try before going for out and out civil disobedience, for example lobbying to have a law changed, but this can take years and so it's not always the best option.
For a law to be considered unjust I'd say it would have to go against the principle that all people are created equal - if a law makes it legal to discriminate against anyone based on their color, religion, sexuality etc then it's obviously unjust, and should be protested. Laws that require you to act against your conscience are a bit more of a grey area, as we'd like to think we all have a good moral code, but the truth is some people don't! At least not by my standards... So something that goes against my conscience might be something very different from something that goes against another person's conscience. For example, I think laws that allow torture are unjust laws but there are many people out there who would disagree with me. Having said that, I think for some people the death penalty is appropriate - not in the numbers we have in this country, or anything like it, but in some cases, yes. But that's just me - and I know this is something that many people would disagree with me on, too.
Every law is going to curtail people's freedom in one way or another, that is the whole point of laws - preventing people from harming others by their actions. But if we can see that a law harms some people instead of protecting them, then it is most likely an unjust law and should be protested, either by lobbying or civil disobedience if needs must. Occupy!





