For this Introduction, I undertake to look a bit more broadly at recent data. The best sources of demographic information about prisoners are the various surveys and censuses conducted by the U.S. Department of Justice Bureau of Justice Statistics (BJS). While no BJS publication directly addresses the issue, and no BJS dataset allows its full analysis, it is possible to glean something from the most recent BJS prison census, the 2005 Census of State and Federal Adult Correctional Facilities.
Schlanger, Margo. "Prison Segregation: Symposium Introduction and Preliminary Data on Racial Disparities." Mich. J. Race & L. 18, no. 2 (2013): 241-50.