Sandy Berger (search), President Clinton's national security adviser who was once entrusted with the nation's most sensitive secrets, was fined $50,000 Thursday for taking classified documents from the National Archives.

U.S. Magistrate Judge Deborah Robinson handed down the punishment in federal court, stiffening the $10,000 fine recommended by government lawyers. Under the deal, Berger avoids prison time but he must surrender access to classified government materials for three years.

"The court finds the fine is inadequate because it doesn't reflect the seriousness of the offense," Robinson said, as a grim-faced Berger stood silently.

She also sentenced Berger to two years' probation and 100 hours of community service.

Earlier in the hearing, Berger made a short emotional plea that admitted fault and expressed remorse for his crime.

"I let considerations of personal convenience override clear rules of handling classified material," said Berger, calling his actions a lapse of judgment that came while he was preparing to testify before the Sept. 11 commission (search) last year.

"In this case, I failed. I will not again," he said.

The sentencing capped a bizarre sequence of events in which Berger admitted to sneaking classified documents out of the National Archives (search) in his suit, later destroying some of them in his office and then lying about it.

Berger's lawyer, Lanny Breuer, said his client will not appeal the sentence.

The Bush administration disclosed the investigation in July 2004, just days before the Sept. 11 commission issued its final report. Democrats claimed the White House was using Berger to deflect attention from the harsh findings, with their potential for damaging President Bush's re-election prospects.

Initially saying his actions were an "honest mistake," Berger later pleaded guilty in April to a misdemeanor of unauthorized removal and retention of classified material, which contained information relating to terror threats in the United States during the 2000 millennium celebration.

During Thursday's hearing, Breuer characterized Berger as an official eager to get the facts of the Sept. 11 attacks right when he improperly took classified documents and handwritten notes from the Archives.

"The tragedy of 9/11 weighed heavily on him," Breuer said.

Robinson repeatedly questioned Breuer and government lawyers about a provision in federal law that calls for examining a defendant's financial background when issuing punishments. Both attorneys responded that they believed a $10,000 fine was still appropriate.

The Associated Press first reported in July 2004 that the Justice Department was investigating Berger. The disclosure prompted Berger to step down as an adviser to the campaign of Democratic presidential candidate John Kerry.

Clinton was among the Democrats who questioned the timing of the disclosure of the Berger probe three days before the release of the Sept. 11 report. Leaders of the Sept. 11 commission said they were able to get every key document needed to complete their report.