The probe into the minister's well-known militant past centers on his testimony at the Frankfurt trial of a former fellow radical who later turned terrorist. Fischer's courtroom statements, which some claim are false, have prompted opposition calls for his resignation that he has so far brushed off.
"I don't expect the resignation of the minister," spokesman Andreas Michaelis told reporters, adding that Fischer has sought legal counsel although he believes his testimony last month "holds up."
"We want a preliminary investigation. ... We view this prospect with great calm," he said. "The question that has been out there for weeks can only be cleared up in this way."
Even prominent conservatives were reserved about using the imminent probe to increase pressure on Fischer to step down. "Let's let the investigation proceed," said the head of the ultraconservative Christian Social Union, Edmund Stoiber. "It can be withdrawn or turn out to be unfounded."
Parliament President Wolfgang Thierse was notified by prosecutors about the prospect of a criminal investigation Friday, said Helmut Winkelmann, secretary of the parliamentary immunity committee. The probe can be launched within 48 hours if there are no formal objections, but Fischer the most prominent member of the Greens party could not be indicted unless parliament votes to lift his immunity.
Members of the committee could stop the investigation if they feel it is unfounded or politically motivated, although both Social Democratic and opposition Christian Democratic members of the panel said that was unlikely.
"As long as Fischer twists and turns like an eel, prosecutors are the qualified authority to ensure it is cleared up," said Laurenz Meyer, secretary-general of the opposition Christian Democrats.
The last time such procedures were invoked was a year ago for ex-Chancellor Helmut Kohl, the focus of a financial scandal after admitting accepting anonymous donations. Bonn prosecutors reached a deal with Khl earlier this month for him to pay a 300,000 mark ($140,000) fine to end a criminal investigation into breach of trust charges.
The probe would focus on Fischer's testimony Jan. 16 as a character witness at the murder trial of Hans-Joachim Klein, where he said never encountered members of the violent Red Army Faction during his radical days in the 1970s including Margrit Schiller, who later joined the group.
But after those statements were challenged in media reports citing anonymous sources, Fischer later said he could not rule out having met Schiller.
Klein was sentenced Thursday to nine years in prison for his role in a 1975 attack on an OPEC ministers' meeting in which three people were killed. At the trial, Fischer said he had urged Klein not to join a terror organization and distanced himself from those who advocated violence.
In remarks at Klein's sentencing, Judge Heinrich Gehrke criticized attempts to start an investigation against Fischer for his testimony.
"I regret that people who speak honestly and seriously about their past, and who have overcome it impressively, are subjected to extreme difficulties because they spoke out," Gehrke said. Prosecutors in Frankfurt weren't expected to make an official statement on the issue until Monday, said spokesman Job Tilmann.
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