State and federal laws requiring mandatory minimum prison terms leave little room to consider differences among crimes and criminals, a commission studying problems in the criminal justice system found.
More people are behind bars for longer terms, but it is unclear whether the country is safer as a result, the ABA said.
Long prison terms should be reserved for criminals who pose the greatest danger to society and who commit the most serious crimes, the report said. States and the federal government should find alternatives to prison terms such as drug treatment for many less serious crimes.
"The costs of the American experiment in mass incarceration have been high," the report said.
It said states and the federal government spent $9 billion on jails and prisons in 1982 and $49 billion in 1999, an increase of more than 400 percent.
The likelihood that someone living in the United States will go to prison during his or her lifetime more than tripled to 6.6 percent between 1974 and 2001, the report added.
The report, nearly a year in the making, follows up on blunt criticism of the criminal justice system that came from an unlikely quarter last year. Supreme Court Justice Anthony M. Kennedy, a moderate conservative placed on the court by President Reagan, asked the nation's largest lawyers' group to look at what he called unfair and even immoral practices throughout the criminal justice system.
The ABA has responded with a lengthy study and recommendations for changes in sentencing laws and in other areas. In the case of mandatory minimum sentencing laws, state legislatures and Congress would have to pass new legislation to repeal the existing laws.
The ABA, the nation's largest lawyers' group with more than 400,000 members, will vote in August on whether to adopt the recommendations as official positions of the organization. The ABA's policies are not law, but are influential.
"For more than 20 years, we have gotten tougher on crime," said ABA President Dennis Archer. "Now we need to get smarter."
The ABA report also urged governors and the president to pardon more deserving prisoners, and recommended stronger efforts to reduce racial disparities in sentencing and in the prison population.
Based on current trends, a black male born in 2001 has a one in three chance of being imprisoned during his lifetime, compared with a one in six chance for a Latino male and one in 17 for a white male, the report noted.
According to the federal Bureau of Justice Statistics, at the end of 2001 some 2,166,260 people were incarcerated in the United States. Most of them were in state prisons (1.2 million) or local jails (665,000).
An end to mandatory minimum prison terms is among the report's most specific recommendations, and probably one of the hardest to achieve.
Addressing the ABA last summer, Kennedy pointed to what he called overly harsh prison terms for nonviolent drug offenders, and specifically denounced mandatory minimum sentences.
"Our resources are misspent, our punishments too severe, our sentences too long," Kennedy said then.
CBS News legal analyst Andrew Cohen notes that the high court is expected to decide in the next few days on a case related to this issue.
"So the ABA isn't just whistling in the dark here and we actually may see some changes in the future," Cohen said.
Mandatory minimum sentences have proliferated over the past two decades, and are often politically popular. They often respond to a specific new threat or phenomenon, such as the spread of crack cocaine in the 1980s.
In 1986, Congress required certain long federal prison terms for possession of crack that were longer than sentences for the powder form of the drug. For example, possession of just five grams of crack yields a mandatory prison term of at least five years. A person must be caught with 500 grams of powder cocaine to merit a similar sentence.
California passed a well-know mandatory minimum sentence, the "three strikes" law, in which a person who commits a felony after having been convicted of two or more previous felonies gets life in prison.
Activists in New York State have been working for years to roll back the 1970 Rockefeller drug laws, which impose harsh sentences like 15 years for possession of as little as four ounces of certain substances.