So, I have set down some basic thoughts about this situation with our neighbor that can extend into other areas as well:
1. We must stand against evil wherever we find it.
2. We must fight evil in a way in which we do not become evil ourselves. (Do not repay evil for evil).
3. If laws exist that address this particular evil, we must insist that those laws are enforced. (The reason we do not have many examples of this in Scripture is that our society has been built on laws that were taken from God's laws, which was not the case under the Romans).
4. We must obey all just laws ourselves.
5. We must resist or break laws that are not just - that are against God's laws. (For instance, it was legal to murder Jews under the Nazis, but this could not be considered to be a 'just' law, and therefor must be broken by Christians).
Justice is, at its finest, the full expression of agape love. It brings about the creation of a community of shared values based upon love. We will love others in spite of the fact that their sin brings us suffering. When their sin is in direct violation of God's laws, it must be confronted. If the consequences of their sin brings them to repentance, so much the better.