Dephys 49

Dephys 49 was a human colony in the time of the Second Empire. The laws there allowed citizens to avoid paying taxes if they spent a year outside legal jurisdiction. At first this meant in space or outside the planet's influence, but was later limited to spending a year in the Time Vortex. The Second Doctor encountered five people from Dephys 49 who were doing this: Brachinnen, Ferrix, Kandol, Kya and Leeth. (PROSE: Vortex of Fear)