The Inter-American Court of Human Rights is expected to rule early this month on whether Lori Berenson, a New Yorker serving a 20-year sentence on charges of helping a rebel organization, received a fair trial under Peru's anti-terrorism laws.

The case is sensitive for President Alejandro Toledo, whose opponents are demanding that he keep Berenson behind bars regardless of the ruling by the Costa Rica-based court, a decision that will be binding. The ruling could uphold Peruvian court proceedings or side with Berenson. Government attorneys said they expected to lose the case, with a retrial ordered.

Berenson, 35, imprisoned since November 1995, was accused of collaborating with the Tupac Amaru Revolutionary Movement , a small rebel group that is now defunct. A military court found her guilty in early 1996 and sentenced her to life. She was retried in 2001, this time by a civilian court, and sentenced to 20 years in prison.

Her defense team, led by Ramsey Clark, the former U.S. attorney general, argues that she should be released because her trials failed to meet international standards for due process, including the fact that she was tried twice for the same crime.

Berenson has maintained that she is innocent of the charges and says she has been used as a pawn by the Peruvian government to distract attention from other issues.

If Peru is told to restore her rights, she could be released and expelled from the country. The government could also disregard the ruling and withdraw from recognizing the court's jurisdiction. Analysts have said, however, that the most likely scenario, was for the government to accept the ruling and order her to stand trial for a third time.

During a recent interview at the maximum-security prison in Cajamarca, 350 miles north of Lima, where she has been jailed for nearly two years, Berenson said she may might refuse to stand for a third trial.

"I am opposed to a third trial," she said. "I think it can be safely assumed that I will not receive a fair trial, and I am not willing to have my family subjected to another long legal battle. If I am forced to stand trial, I will do so without a lawyer."

Analysts said freeing Berenson would be political suicide for Toledo, who is the least popular president in Latin America with only 12-percent support. They said he would be labeled immediately as soft on terrorism and give his opponents more ammunition to attack his already shaky administration.

Marcos Ibazeta, the judge who presided over Berenson's 2001 retrial and denies any political influence in the 20-year sentence she received, said that the court's decision would set the stage for the most controversial retrials, including that of the founder and leader of the Shining Path rebel group, Abimael Guzman.

"What the Inter-American Court decides on the Berenson case will define everything." he said.

Berenson's defense team also has an alternative that would save the country from having to deal with a loss in Costa Rica. Her lawyers have sent a letter to the government calling for Berenson to be released before the Inter-American Court hands down its sentence, thereby avoiding the ripple effects the decision will certainly have for the country.