Competing jurisdictions. The market will decide the law.
They (the market) actually already do. That's how we have republics, democracies, socialism, communism or any other type of -ism or governing. The basic premise of the law is force legalized. Which is to say, your version which you execute upon another man (for reasons justified by you) is merely competing with another man's version of the law. The question is, if you're right, then yours should be the ipso facto standard. Unfortunately that doesn't suffice. Truth doesn't make things happen, implementation does. That requires real force applied to real objects (including people in some instances).
Saying that we can compete for the definition of the law is to apply force your way, or their way, or some other way. In the final analysis and outcome of things, it isn't so much that you may be right (no harm, no injury, do as ye will) it's who has the superior force.
You and your collective force (mutual solidarity) must merely have superior strength, not superior truth. We can't break the laws of nature (as far as I know), but we can violate each others basic human rights. For that -collectively- we must have a standard, and then, and only then can we compete for services (governmental or otherwise) under that premise and principle.
Competing jurisdictions would work well if the boundaries to those 'jurisdictions' couldn't be invaded or penetrated by external forces. If that were possible, we could all start our own societies and see who comes out on top. Sadly, this is near impossible