Report: There is a very weak relationship between higher incarceration rates and lower crime rates. Although studies differ
somewhat, most of the literature shows that between 1980 and 2000, each 10 percent increase in incarceration rates
was associated with just a 2 to 4 percent lower crime rate.
Since then, only one empirical analysis (a study that requires
corroboration) has examined the relationship between
incarceration and crime.
Overall, the increased use of
incarceration through the 1990s accounted for between 6
and 25 percent of the total reduction in crime rates. Since 2000, however, the increased use of incarceration accounted
for nearly zero percent of the overall reduction in crime.