BOGOTA, COLOMBIA, JAN. 21 -- The first drug trafficker to surrender under President Cesar Gaviria's promise of to waive extradition has been released from prison by a judge after less than two months, raising questions about the Colombian judicial system's ability to punish powerful traffickers.

The ruling was made Jan. 11 but not made public until today, when the government announced it would appeal and would charge the judge with the felony of "willful and knowing violation" of the law.

Freeing of the convicted Gonzalo Mejia stunned federal officials, who called it illegal and said it could seriously undermine Gaviria's policy here and abroad. They voiced fears that it also could limit international cooperation in the cases of two of the world's most powerful drug traffickers, brothers Fabio and Jorge Luis Ochoa, the reputed leaders of the Medellin cocaine cartel, who turned themselves in under the same government policy.

"The government is worried, because, obviously, it affects the credibility of our policy," said a senior official today. "We acknowledge there is a problem, and we are doing everything we can to correct it."

Attorney General Carlos Gustavo Arrieta said he was bringing criminal charges against the judge who, he said, illegally paroled Mejia. Under indictment in Florida, Mejia confessed to five counts of cocaine trafficking, but served only 44 days of his three-year prison sentence. Under Colombian law, those jailed for drug trafficking are not eligible for parole.

The judge, Aristides Betancur, resigned his post last week after granting Mejia parole. A source monitoring the government investigation said there was no evidence that the judge had been bribed but speculated that he may have felt his life to be at risk if he kept Mejia in jail. The drug cartels repeatedly have intimidated, bribed or killed judges who stood in their way.

"We are enormously concerned because this is not in line with the purposes of the government policy and can be seen as a mockery of justice that has a negative impact on the process," Arrieta said in a press conference.

Mejia, described by the official as a "middleman in a mid-sized organization," initially was sentenced to six years in prison, the minimum time for drug trafficking. His sentence was reduced by half because of his confession, and because he turned over $60,000 in cash and a pick-up truck.

In September, Gaviria promised that traffickers who turned themselves in and confessed to a crime would not be extradited to face charges in the United States and would receive reduced sentences.

The policy has won broad support in Colombia and parts of the U.S. government, but national and international law enforcement officials have expressed skepticism that Colombia can effectively try and punish the traffickers.

Of special concern is whether traffickers who surrender will receive punishments that fit their crimes, and Gaviria says his policy will work, and the criminals receive stiff sentences, only if the United States and other countries turn over their evidence to Colombian authorities.

This is especially true in the case of the Ochoa brothers. While both are listed as among the U.S. list of 12 most wanted traffickers, Fabio faces no criminal charges in Colombia and Jorge Luis faces only minor charges. The latter has been arrested twice, and both times managed to slip away, once under circumstances almost identical to that of Mejia's parole.

But the evidence-sharing plan has hit serious snags, which the Mejia case is likely to exacerbate.

U.S. and European narcotics experts fear that if they turn over all their evidence and it is improperly used or the Ochoas are suddenly freed, the evidence could not be used again in future trials because that would mean trying the person twice for the same crimes.

Use of some evidence could also damage other cases where several people are tried for the same crime, the officials said.

"The double-jeopardy issue is a serious concern," said a U.S. narcotics expert working with the Colombians. "Initially, the Colombians thought we would just take a wheelbarrow and give them everything we have," he said. "Neither side was aware of how complex this would be."