Rey Reynoso wrote a post a few months ago on Christians and civil disobedience that I'd wanted to respond to in a post of my own, but I never did. I wanted to put a link up to it before it gets too far distant in time, even if I can't respond in depth.
The one thought that I will say is that I think Rey has an interesting proposal, but I don't think it gets around the Rosa Parks problem. The gospel wasn't at stake for her, so I think on Rey's account she still comes out as immorally violating the law. That's the biggest problem case for the Christian view of submission to authorities, since so many people think what she did was not just good but heroic. But I do think the biblical view is that it was wrong, despite being well-intentioned. (The second-biggest case I can think of for contemporary Americans is the American Revolution, which I also think was immoral on biblical grounds but is certainly supported by most Christians in the U.S.)