The Solar System Congress
The Solar System Congress, or SSC, is more analogous to a United Nations rather than a true governing body of the solar system. This elected body made of representatives from every major colony in the solar system does create laws and enforces them through the ISSP. But these laws only apply to open space. Besides the ISSP, the main power behind the SSC is their control of the Gate system, capable of cutting off any colony that would openly oppose them.