From the introduction:
Newcomb: Prison Planet details an Imperial prison world in the Solomani Rim subsector, Newcomb / Banasdan 2913. There are over 301 billion inhabitants in the Solomani Rim, and the 40,000 or so relatively law-abiding inhabitants of Newcomb reside alongside around 1,700 of the most dangerous captive criminals among that population.
The Solomani Rim is of course politically divided between the Imperium and the Solomani Confederation, and this is invariably refl ected upon Newcomb. The prison facility is a rough and ready institution, socially isolated, politically neglected, and severely lacking in investment over a number of years. It is a run-down, relatively low technology facility, operated by people who don’t want to be there, but have no choice other than to be.