People serving long federal prison terms for crack cocaine call it that "new crack law."

However, it's not exactly a law that has shaken up the federal judicial system. It was a move by the U.S. Sentencing Commission and Congress' hesitant agreement to bring the potential prison terms for crack cocaine closer to the less harsh punishment for powder cocaine.

Until March, the average sentence for a crack cocaine conviction was 129 months in prison. The average prison sentence for powder cocaine was 86 months.

Now that reductions have been called for, it's up to federal district judges to decide how to make them, and who among the thousands of people already serving prison terms should get them.

The sentencing guidelines that went into effect Nov. 1, 1987, set the punishment ranges for crack and all federal crimes. Anyone sentenced since then can petition the federal judges for a reduction, said Richard Long, chief probation officer for the Southern District of Georgia.

"It's a large number of cases," Mr. Long said of those who can file petitions in the southern portion of the state.

So far in the Southern District of Georgia, the judges have considered 97 petitions and granted reductions to 54 people, according to the most recent data collection by the U.S. Sentencing Commission. That's just in the first month since the reductions became retroactive.

Augusta-area attorney Charles Lyons said the sentencing reductions aren't going to throw open the prison gates. Those with a number of prior convictions or those people who armed themselves while dealing drugs probably won't get any reductions, he said.

"It's not an automatic across-the-board reduction for everyone," Mr. Lyons said.

It is still too early to draw any meaningful conclusions, officials say, but it appears the reductions averaged two to three years, according to data collected by the U.S. Sentencing Commission.

Crack cocaine sentences have been based on the quantity of drugs, Mr. Long said. In the federal system, probation officers play a major role in how judges determine punishment. The probation officers prepare pre-sentencing reports that detail an individual's personal history, outlines all of the elements of the crime, and calculates the appropriate sentencing range.

Deciding whether there's merit to a reduction request depends on many variables, Mr. Long said. Criminal history, the amount of drugs and personal responsibility are some factors considered.

Mr. Lyons said a person can still end up with the same sentence after consideration.

The federal sentencing guidelines provide sentencing ranges. For example, three years ago a particular person faced a sentencing range of 108 to 150 months and the judge imposed a 130-month sentence. After requesting a reduction, the person may now have a sentencing range of 90 to 130 months. But the judge could decide 130 months is still the appropriate sentence, Mr. Lyons said.

Mr. Long said the reductions given so far have ranged from six months to four and a half years.

Any person sentenced for a crack cocaine conviction can file a motion with the federal judge who sentenced him.