Baffled liberal criminologists claim there must be a self- perpetuating boom in U.S. prison building, since the percentage of the population in prison (the incarceration rate) rose while crime rates fell. With fewer crimes there should be fewer criminals, and therefore less need for imprisonment. They suggest the prisons are being filled with nonviolent drug offenders.

Other experts say the increase in the U.S. prison population in recent years is one of the reasons crime rates have fallen: imprisonment incapacitates career criminals and deters others from committing crimes.

• Thus from 1980 to 1996, the incarceration rate lurched upward 209 percent, and there was a relatively steady decrease in the serious crime rate of 31 percent.

• As incarceration rates rose 38 percent from 1991 to 1996, the serious crime rate fell 22 percent and the violent crime rate declined 16 percent.

Among violent criminals robbers have the highest recidivism rate, and among perpetrators of serious crimes in general burglars have the highest recidivism rate. Locking more members of these groups up seems to have affected crime rates.

• Burglars have the highest recidivism rate of all serious offenders, at just under 50 percent nationwide.

• When the prison-building boom began in 1980, the burglary rate started to descend, dropping 44 percent from 1980 to 1996.

• In the 1990s, the burglary rate fell 25 percent in just six years.

• Robbers have the highest recidivism rates of any violent offenders, but from 1991 to 1996 robbery rates fell 26 percent.

And contrary to claims that prisons are being filled with nonviolent drug offenders, experts say more than half of the total increase in male prisoners in 1997 came from criminals convicted of violent offenses. Furthermore, a 1997 Arizona law requiring the release of all first-time drug offenders not previously convicted of a felony was found to apply to only 53 inmates in the state's prisons.

Source: Andrew Peyton Thomas, "More Time, Less Crime," Weekly Standard, November 30/December 7, 1998.