A portrait of Fred Korematsu presented at the National Portrait Gallery in Washington, D.C. Mandel Ngan/AFP/Getty Images hide caption

itoggle caption Mandel Ngan/AFP/Getty Images

When state prison populations were at their peak, prisons like San Quentin in California used gymnasiums to house inmates in bunks. Now it's the federal prison system that's overcrowded. The Bureau of Prisons says it's 35 to 40 percent over capacity. Eric Risberg/AP hide caption

itoggle caption Eric Risberg/AP