It is difficult to argue that incarceration decreases crime. Despite a national expenditure of $46 billion per year, most experts agree that prisons have done little to make life safer.
A recent study by the University of Texas found that while the number of inmates has grown by over 300 percent since the late 1970s, growth in number of prisoners is responsible for no more than 27 percent of the recent drop in crime. In fact, in states with the fastest growing prison populations, crime did not decrease. For example, in West Virginia, incarceration increased by 131%, but crime dropped only 4%; in Virginia, incarceration rose just 28%, but crime dropped 21%