Washington - A woman serving a 27-year prison term for a crack cocaine conspiracy is asking President Barack Obama to use his power of forgiveness for the first time since taking office to commute her sentence.

Two federal judges have called the prison term for Hamedah Hasan, formerly known as Stephanie Lomax, excessive and would have imposed a 12-year sentence. But they were hemmed in by federal law that punishes crack crimes more heavily than those involving powder cocaine.

Now Hasan and a group that includes civil rights advocates and law professors say Obama should use the president's power, enshrined in the Constitution, to shorten her sentence and address the disparity in prison terms for crack and powder cocaine.

Obama has called for Congress to eliminate the disparity, but the American Civil Liberties Union and others in the group backing Hasan argue that while bills to do that languish on Capitol Hill the president should use the pardon power to bring sentences into line on his own.

Like Presidents Bill Clinton and George W. Bush before him, Obama did not make use of his pardon power in his first year in office.

Hasan was convicted in 1993 for her role in a multistate conspiracy to deal crack cocaine. She received a life sentence that was shortened to 27 years. She had no prior criminal record and, had she been convicted of the same crime involving powder cocaine, would have been released from prison by now, her supporters say.

In 1999, U.S. District Judge Richard Kopf tried to lower Hasan's sentence to 12 years, but was overruled by the 8th U.S. Circuit Court of Appeals. Kopf is supporting Hasan's plea to Obama.

Last year, U.S. District Judge Laurie Smith Camp took another look at Hasan's case and initially agreed to the same term as Kopf, which would have resulted in Hasan's release.

Five days later, however, Camp said the law prohibited her from doing what she wanted. In her order, the judge said, "This acknowledgment is made with profound regret and with sincere apology to the defendant, Hasan."