The United States, with less than 5 percent of the world’s population, has about one-quarter of its prisoners. As you noted, the US has the highest incarceration rate in the world. Over 2.4 million persons are in state or federal prisons and jails - a rate of 751 out of every 100,000. Another 5 million are under some sort of correctional supervision such as probation or parole (PEW 2008). The US remains the last of the post-industrial so-called First World nations that still retains the death penalty, and we use it often. Nearly 3,500 inmates await execution in 35 states and at the federal level. It was not until the early 21st century that the US abolished capital punishment for juveniles and those with IQs below 70.
One in every 35 adults is under correctional supervision and one in 100 adults is in prison. Looking at the racial dynamics, one in every 100 black women, one in 36 Latino adults, one in 15 black men, and one in nine black men ages 20 to 34 are incarcerated (Pew 2008). Approximately 50% of all prisoners are black, 30% are white and 17% are Latino (Bureau of Justice Statistics 2007). Notably, the race of victim, race of offender, and social class remain the best predictors of who will receive the death penalty. Nancy A. Heitzeg, professor at St. Catherine University in Minnesota in March 2010 interview "The Racialization of Crime and Punishment"