When a Berlin court on Wednesday acquitted Ihsan Garnaoui on charges of trying to form a terrorist organization, law enforcement officials and experts rolled their eyes.

In its decision, the court said that the 34-year-old Tunisian, arrested by police in March 2003, had planned "to commit at least one attack in Germany using explosives," but said there was not enough to convict him on charges of forming a terrorist group.

But Garnaoui won't be walking free. Using a strategy analysts say should be employed more in coming terror trials, prosecutors pinned him on charges of tax evasion, passport fraud and illegal possession of a gun. The convictions earned him a sentence of three years and nine months and meant he would be deported after getting out of jail.

"They didn't get him on the most interesting charge, but on a number of other charges," said Hans-Jörg Albrecht, director of the Max Planck Institute for Foreign and International Criminal Law. "They got Al Capone on charges like tax evasion, as well. Not on the more serious crimes he may have committed."

Legal shortcomings in terror trials

The strategy could show the way for a more effective way of prosecuting terrorism suspects at a time when the German judiciary is under pressure to produce some success stories, said Albrecht. Last year, Abdelghani Mzoudi, an accomplice to the planners of the Sept. 11 terrorist attacks was acquitted by a Hamburg court and Mounir el Motassadeq (photo), the only person worldwide convicted in connection with the 2001 attacks, won retrial because the court didn't hear crucial testimony.

The acquittals have frustrated German government leaders eager to show that they are winning the fight against terrorism. There has been talk of tweaking the legal system to lower the burden of proof in terror trials, something considered in other countries such as the United Kingdom.

"You find the same problems in English, American and French trials as well," said Albrecht. "It's a problem that every court has."

The difficulties lie in classifying a group of people who might share the same ideology or beliefs as a criminal organization. After establishing that Garnoui, who had visited Afghanistan in 2001 and divorced his liberal German wife in 2003, held extremist beliefs, prosecutors were unable to portray him as the ringleader of others with similar attitudes.

Two undercover agents too unbelievable

Police, who had been tailing him, broke into his apartment to arrest him on March 20, 2003, and found bomb-making instructions and mobile phones that they allege could be used as triggering devices. But the testimony of two undercover agents, who were not present at the trial, was deemed too thin by the court. His plans to carry out bomb attacks, though partly proved by the prosecution, were not enough for a harder charge.

"It's clear he planned something, but planning alone is nothing," Michael Rosenthal, the defense lawyer on the trial, told reporters, according to the Associated Press. "What was missing was the start of the execution."

For Kai Hirschmann, a security expert with a focus on terror investigation strategy, the failure is another reason for Germany to radically re-think its legal structure. Following the realization that the Sept. 11 attacks were planned in Hamburg, the government passed two security packages that eased the burden on prosecutors. Hirschmann said that legislation needs another clause.

Punishing Jihad-ism

"We need to be able to charge people for sharing this Jihadist ideology, which automatically leads to violence," he said. "We need to treat Jihadism in the same way we do national socialism."

Such a major change would require an unusual alliance of the government and its biggest opposition party and is unlikely in the coming years. For the time being, said Albrecht, lumping major charges like terrorism, with smaller charges might be the best way for lawyers working within the current system.

"It's a strategy that is more promising," he said. "Especially against terrorist or criminal organizations that don't reveal themselves as such."