The U.S. prison population edged up slightly last year, though the number of total inmates dropped in 20 states, including New York, Georgia and Michigan.
Justice Department figures released Tuesday show the overall state and federal prison population stands at a record 1.6 million and is still rising, but the rate of growth is slowing as state authorities look for cheaper ways to mete out justice.
If you add in those people in jails _ where some are held while they await trial _ the total number of people behind bars comes to 2.3 million.
The government figures show one out of every 133 U.S. residents was in prison or jail at the end of last year.
The statistics are the latest evidence that the rapid growth of prisons seen in the 1990s has cooled significantly in this decade.
The prison population grew less than 1 percent last year. The previous decade saw the inmate population grow by an annual average of more than 6 percent.
Ram Cnaan, a professor at the University of Pennsylvania's School of Social Policy and Practice, said the slowing trend shows politicians are confronting a painful truth about prisons.
"They simply cost too much," said Cnaan. "If you can prevent opening a new prison, you can save lots of money."
Both liberals and conservatives are increasingly searching for alternative sentencing programs, like treatment or monitoring, he said.
"It's not ideological, it's pragmatic," said Cnaan. "This is the first time that we have alliances on the right and left on this issue, and it's the money that has forced the issue."
The states with the largest increases in prison population were Pennsylvania, Florida and Arizona, whose one-year increases were all greater than the federal prison system, which grew by 1,662 inmates.
Of the three states that lost the most prisoners in 2008, New York shed 2,273, Georgia 1,537 and Michigan 1,495.
One group that saw a big jump in incarceration were immigration detainees, which jumped 12 percent. About 34,000 people were held last year in an Immigration and Customs Enforcement lockup or a contracted holding facility. About a third of those detainees were originally from Mexico, the Justice Department said.
While more prisoners were locked up, officials also released more _ some 735,454 prisoners, a 2 percent increase over 2007.
Among those releases, the number of those freed without conditions increased 8 percent.
On the Net:
Justice Department's Bureau of Justice Statistics: http://www.ojp.usdoj.gov/bjs/