A federal appeals court yesterday threw out the convictions of five alleged Cuban agents, saying pervasive anti-Castro sentiment in Miami prevented the group from getting a fair trial there.

The ruling from the 11th U.S. Circuit Court of Appeals in Atlanta was met with praise from defense attorneys and outrage from opponents of the Cuban regime.

“Waves of public passion … flooded Miami both before and during this trial,” the three-judge panel wrote in overturning the men’s June 2001 convictions following a seven-month trial. “Despite the district court’s numerous efforts to ensure an impartial jury in this case, we find that empaneling such a jury in this community was an unreasonable probability because of pervasive community prejudice.”

Judges Phyllis Kravitch, Stanley Birch Jr., and James Oakes said Cuban exile organizations had created an atmosphere in Miami that might have intimidated jurors. “The perception that these groups could harm jurors that rendered a verdict unfavorable to their views was palpable,” the judges wrote.

The appeals court said events like federal agents’ seizure of a Cuban boy, Elian Gonzalez, from his relatives’ home in Miami in 2000 contributed to a “perfect storm” that tainted the espionage trial.

The defendants, Gerardo Hernandez, Antonio Guerrero, Ramon Labanino, Rene Gonzalez, and Fernando Gonzalez, conceded in court that they were agents of the Cuban government. They said the primary duties of their cell, dubbed “La Red Avispa,” or the “Wasp Network,” involved monitoring and infiltrating anti-Castro groups. Defense attorneys argued at trial that such activities did not amount to espionage.

However, prosecutors attempted to tie the “Wasp Network” to the deaths of four Cuban exiles in 1996 when a Cuban fighter shot down the aircraft of an anti-Castro organization, Brothers to the Rescue. Brothers to the Rescue was one of the groups the Cuban agents penetrated.

Jurors deliberated for five days before convicting the men on all charges, including a murder conspiracy count brought against the alleged ringleader, Mr. Hernandez.

Messrs. Hernandez, Guererro, and Labanino, received life sentences. Fernando Gonzalez was sentenced to 19 years, while Rene Gonzalez got 15 years. Those sentences will soon be vacated, unless the government persuades the full bench of the 11th Circuit or the Supreme Court to hear the case.

Rep. Lincoln Diaz-Balart, a Republican of Florida, yesterday charged that the appeals court ruling amounted to discrimination against Cuban-Americans. “Basically, it says this community is incapable of holding a fair trial. And that shocks the conscience,” Mr. Diaz-Balart said. “It’s almost like saying that because tyranny is evil that in a community where there are people who fled that tyranny, a fair trial cannot be held.”

Mr. Diaz-Balart noted that there were no Cuban-Americans on the jury that convicted the men. “The evidence was overwhelming. They’re spies for a terrorist regime,” he said.

A spokeswoman for the U.S. Attorney’s office in Miami, Alicia Valle, said prosecutors were reviewing the ruling and had no immediate comment.

In a conference call with reporters, defense lawyers praised the court’s decision as a tribute to the American justice system.

“The court of appeals just went through point by point just showing how this trial was infected by prejudice from the beginning until the end,” an attorney for Mr. Hernandez, Paul McKenna, said. The defense attorney said he was particularly heartened that the judges pointed to one courtroom incident in which a witness involved with Brothers to the Rescue, Jose Basulto, suggested that the lawyer, Mr. McKenna, was acting on behalf of the Cuban intelligence service.

Mr. McKenna said the defendants, who are serving time at various prisons around the country, would have to be returned to Miami and given all the privileges accorded to pre-trial inmates. The lawyer said he is exploring the possibility of some form of supervised release for his client, who has been in jail for seven years.

A lawyer for Mr. Guerrero, Leonard Weinglass of Manhattan, said the appeals court decision broke new ground. “This is really a historic opinion. Never before in the history of the United States had a federal court of appeals reversed a trial court’s finding with respect to venue,” he said.

In an interview with The New York Sun, Mr. Weinglass said the court’s ruling could have an impact on the ongoing trial in Tampa of a former college professor, Sami Al-Arian, and three other men accused of operating the American wing of a terrorist group, Palestinian Islamic Jihad. In that case, defense lawyers also sought a change of venue because of the extensive publicity Mr. Al-Arian’s long-running legal saga has received in the Tampa area.