The answer is: In 2005, an estimated 747,000 private prisons were in the United States; a number that has been increasing since 1970 with the privatization of prisons (for example, since anti-drug laws are stricter) for the growing number of prisoners, who by 2008 had increased to 2,500,000 prisoners. The private prisons business greatly affects the penitentiary system because it brings a lot of money to private prisons in exchange for long and unjustified sentences of almost harmless criminals (such as shop stealers, without violence and being their first time) and clearly, these prisons they profit from prisoners on many occasions.