Random Prisoner/Census Data

Obviously there are a lot of issues with the census and those issues are particularly serious when you deal with urban environments but I came across this randomly and don't have time to adequately investigate it now so will get back to it later, but: "Sixty percent of Illinois' prisoners are from Cook County (Chicago), yet 99% of the state's prison cells are outside the county." Now, evidently, but not entirely clear from this piece, the prisoners are counted as residents of the place where the prison is located, which is kind of technically logical and yet, probably terribly flawed. This is particularly true when the census data is used for the purposes of drawing districts and providing representation and the prisoners aren't able to vote. It's all very bizarre and I will return to it in depth later.