[F]or some civil liberties groups and the nonprofit Prison Policy Initiative, which has analyzed the last census numbers, counting inmates in prisons distorts population numbers in New York and several other states. Rural areas are shown to be more populous than they are, these critics say, while urban areas -- which produce most of the inmates -- are routinely under-counted.http://www.washingtonpost.com/wp-dyn/content/article/2009/04/25/AR2009042501403.html
States and counties rely on population numbers from the census to draw their legislative districts. In New York and some other states, Republicans continue to have clout in legislatures because they are elected from safely conservative, rural districts even as those areas lose people. The exception to that population decline: inmates, whose numbers have grown because of tough mandatory sentencing laws.
There is an unobserved fight going on over where prisoners "live", in the urban communities they mostly come from or in their mostly rural prison cells.
Forget all other issues and factors - - the outcome of the debate over where prisoners are counted for redistricting purposes could determine who controls Congress after the post-census redistricting.