The U.S. Sentencing Commission voted unanimously yesterday to allow federal prisoners convicted on crack cocaine charges to petition for reduced sentences, setting the stage for the potential early release of almost 20,000 prisoners nationwide, including 908 in Pennsylvania and New Jersey.

About 3,800 inmates could be eligible for release from prison within a year after the March 3 effective date. Of those, 141 inmates in Pennsylvania and 16 in New Jersey would be eligible, according to the commission.

Federal judges will have the final say whether to reduce sentences.

The commission said the March date would give judges and prison officials time to deal with public safety and other issues.

The Sentencing Commission voted one day after the U.S. Supreme Court handed down decisions in two highly anticipated drug cases, upholding more lenient sentences imposed by judges who found the guidelines too severe. In one case the justices said federal judges were not bound by guidelines that call for tougher sentences for crack than for powder cocaine. In the second case, the court made it easier for judges to deviate in general from sentencing guidelines that have been the subject of debate for more than two decades.

U.S. District Judge William Sessions of Vermont, one of seven commission members, said the vote on retroactivity would have the "most dramatic impact on African American families."

A failure to act "may be taken by some as particularly unjust," Sessions said before the vote.

One of the issues that has long troubled penal experts and civil rights advocates is the racial ramifications of stiffer sentencing for crack cocaine offenses over powder cocaine cases. Blacks tend to use crack cocaine at a higher rate than whites, who are more likely to use cocaine in powder form.

Several former and current federal judges in Pennsylvania and New Jersey said they welcomed the commission's decision to apply the new guidelines retroactively.

"My feeling is that these people were sentenced unfairly under what was arbitrary and capricious distinction between two types of cocaine," said Steve Orlofsky, a former U.S. district judge for the District of New Jersey who is now a defense attorney in Cherry Hill.

"The way it is now is unfair," said Judge John E. Jones of the U.S. District Court for the Middle District of Pennsylvania, which handles federal drug cases in the central section of the state.

Of those eligible for early release, 94 percent are male and 86 percent are black, with an average age of 35. The average sentence reduction under the revised guidelines would be 27 months - dropping the average time served from 13 years to 10. The Justice Department, which had opposed the retroactive application of the guidelines, said yesterday the decision would make "thousands of dangerous prisoners" eligible for immediate release.

"In addition to the threat to public safety, retroactive application will divert valuable resources from federal courts and prosecutors for resentencing at a time when violent crime is rising in many vulnerable communities around the country," said Craig Morford, acting deputy attorney general.

The commission said it took note of objections raised by the Bush administration, but said there was no basis to treat convicts sentenced before the guidelines were changed in November differently from those sentenced after the change.

The commission established the guidelines in the mid-1980s as a way to create more uniform punishment for similar crimes committed across the nation.

Responding to the view that crack cocaine led to more violent crimes than powder cocaine, the commission incorporated a sentencing structure that imposed the same sentence on a person selling crack cocaine as on a dealer of powder cocaine who sold 100 times that amount.

In April, after years of criticism of racial bias, the commission reversed itself and amended the sentencing guidelines.

That decision was intended to provide "some relief to crack cocaine offenders affected by the disparity created by federal cocaine sentencing policy," the commission wrote.

The Justice Department and some local district attorneys contend the decision could overwhelm the criminal justice system.

"This will cause a whole lot of resentencing that has the potential to create chaos in the system," said Bruce Castor, Montgomery County district attorney and president of the Pennsylvania District Attorneys Association.

Jones, who said drug cases dominate his docket, disagreed.

"We'll have a lot of cases to resentence, but this is not the first time a rule change has been made," he said. "We'll deal with it."

One local prosecutor said he feared the ruling could mean less help from federal authorities.

Brian Mulholland, chief of the narcotics unit at the Camden County Prosecutor's Office, said the U.S. Attorney's Office often takes over some of the bigger state cases because the federal system is tougher - no bail and no parole - and the penalties are stiffer in federal court.

"Perhaps the U.S. Attorney's Office would be less likely to supercede some of our crack cases . . . if their sentencing guidelines are lowered and their guidelines are less than ours," he said.

In New Jersey, the sentences are the same for crack and powder cocaine, he said.

Contact staff writer Amy Worden at 717-783-2584 or aworden@phillynews.com.

Inquirer staff writer Troy Graham contributed to this article, which also contains information from the Associated Press.