After three decades of explosive growth, the nation’s prison population has reached some grim milestones: More than 1 in 100 American adults are behind bars. One in nine black men, ages 20 to 34, are serving time, as are 1 in 36 adult Hispanic men.

Nationwide, the prison population hovers at almost 1.6 million, which surpasses all other countries for which there are reliable figures. The 50 states last year spent about $44 billion in tax dollars on corrections, up from nearly $11 billion in 1987. Vermont, Connecticut, Delaware, Michigan and Oregon devote as much money or more to corrections as they do to higher education.

These statistics, contained in a new report from the Pew Center on the States, point to a terrible waste of money and lives. They underscore the urgent challenge facing the federal government and cash-strapped states to reduce their overreliance on incarceration without sacrificing public safety. The key, as some states are learning, is getting smarter about distinguishing between violent criminals and dangerous repeat offenders, who need a prison cell, and low-risk offenders, who can be handled with effective community supervision, electronic monitoring and mandatory drug treatment programs, combined in some cases with shorter sentences.

Persuading public officials to adopt a more rational, cost-effective approach to prison policy is a daunting prospect, however, not least because building and running jailhouses has become a major industry.