Today the United States holds 25 percent of the world’s prisoners, while it represents only 5 percent of the world’s population. Elizabeth Hinton traces the start of the prison boom to the spring of 1970 when, under the administration of Richard Nixon, the Bureau of Prisons launched a ten-year “Long-Range Master Plan” to expand the prison system based not on rising crime statistics but instead on population-growth estimates based on the census.
https://www.fff.org/explore-freedom/article/the-roots-of-mass-incarceration/
