One of the more interesting questions of the 21st Century will be what sort of law will prevail on permanent space colonies. Thus far, as Gbenga Oduntan, an associate professor of space commercial law at the University of Kent states in a recent piece in the Conversation, the only example of a community in space has been the International Space Station. By agreement of the partners in the ISS, the space station has a commander whose authority is similar to that of a captain of a ship.
Just as an aside, Oduntan’s assertion that the extraction of space resources for transport to Earth is prohibited is a matter that is in serious dispute. American law indicates that anyone who extracts such resources takes ownership of them to dispose of as they will.
The evolution of space law on Moon bases and Mars colonies
The first lunar base, or moon village as the Europeans prefer to call it, will likely have an arrangement similar to that of the ISS, with a rotating commander agreed upon by the partners in the enterprise who will operate like a benevolent tyrant, subject to the authority of Earthside governments.
Some time will likely pass before a base or village on the moon has enough people that would give rise to demands for self-government.
Oduntan does not cover the idea of how a Mars colony, especially a private one, would govern itself except for a brief mention at the end of his piece. “Ultimately, there’s the possibility that colonists won’t be happy being governed by Earth law. What should happen to them – would they be neo-colonialists or simply ‘alien’ in legal terms? Would they or should they form or evolve their own juridical systems while in long-duration flight? Should parliaments on Earth deal with Martian earthlings’ issues on an arms-length basis?”
Actually, it is pretty likely that a group of people who choose to travel 100 million miles to an inhospitable planet to start new lives is going to want to govern themselves from the start.
At some point, perhaps not right away, Mars colonists should be regarded as citizens of their own country, which would have the right to form its own government and conduct diplomacy in order to advance their own interests. They are not going to want to follow the whims of politicians in Washington, Brussels, or Beijing. The idea of Earth authorities trying to exert control across interplanetary distances is laughable at best.
How a Mars government would work
Suppose that someone like Elon Musk succeeds in founding his own private Mars colony. At a certain point, the Mars colonists are going to have to start thinking about how to govern themselves.
The most obvious model for a Martian government would be a constitutional republic on the model of the United States, with the powers of the various branches of government tailored to the realities of living on an inhospitable planet such as Mars.
The Martian Republic would have a president or prime minister, a congress or parliament, and a judicial system. The Martian constitution would spell out in advance the rights of Martian citizens and the obligations of their government.
The Martian Republic will want to establish its national sovereignty over enough territory to sustain its population. It could try to lay claim to the entire planet, but may not have the physical power to enforce such a claim, at first, in the absence of an international agreement. It may be convenient to allow the new nation to manage Mars and its resources, which means that any new colonists who settle at another location would technically be under the sovereign authority of the Martian government.