WASHINGTON, Aug. 1 - As a veteran agent chasing home-grown terrorist suspects for the Federal Bureau of Investigation, Mike German always had a knack for worming his way into places few other agents could go.
In the early 1990's, he infiltrated a group of white supremacist skinheads plotting to blow up a black church in Los Angeles. A few years later, he joined a militia in Washington State that talked of attacking government buildings. Known to his fellow militia members as Rock, he tricked them into handcuffing themselves in a supposed training exercise so the authorities could arrest them.
So in early 2002, when Mr. German got word that a group of Americans might be plotting support for an overseas Islamic terrorist group, he proposed to his bosses what he thought was an obvious plan: go undercover and infiltrate the group.
But Mr. German says F.B.I. officials sat on his request, botched the investigation, falsified documents to discredit their own sources, then froze him out and made him a "pariah." He left the bureau in mid-June after 16 years and is now going public for the first time - the latest in a string of F.B.I. whistle-blowers who claim they were retaliated against after voicing concerns about how management problems had impeded terrorism investigations since the Sept. 11 attacks.
"What's so frustrating for me," Mr. German said in an interview, a copy of the Sept. 11 commission report at his side, "is that what I hear the F.B.I. saying every day on TV when I get home, about how it's remaking itself to fight terrorism, is not the reality of what I saw every day in the field."
Mr. German refused to discuss details of the 2002 terrorism investigation, saying the information was classified.
But officials with knowledge of the case said the investigation took place in the Tampa, Fla., area and centered on an informant's tip about a meeting between suspected associates of a domestic militia-type group and a major but unidentified Islamic terrorist organization, who were considering joining forces. A tape recording of the meeting appeared to lend credence to the report, one official said.
Law enforcement officials have become increasingly concerned that militant domestic groups could seek to collaborate with foreign-based terrorist groups like Al Qaeda because of a shared hatred of the American government. This has become a particular concern in prisons.
The Tampa case is not known to have produced any arrests. But Mr. German, in an April 29 letter to several members of Congress, warned that "the investigations involved in my complaint concern very active terrorist groups that currently pose significant threats to national security."
He also wrote, "Opportunities to initiate proactive investigations that might prevent terrorist acts before they occur, which is purported to be the F.B.I.'s number one priority, continue to be lost, yet no one is held accountable."
The Justice Department's inspector general is investigating Mr. German's case, reviewing both how the F.B.I. handled his complaints and whether he was retaliated against as a result, an official there said.
Donna Spiser, an F.B.I. spokeswoman, said that the bureau "thoroughly investigates all allegations of wrongdoing," but that it could not comment on Mr. German's case because of the continuing investigation.
Some law enforcement officials remain somewhat skeptical of Mr. German's claims. But several prominent senators who have been privately briefed on the case in recent weeks said they were troubled by what they learned.
"Retaliating against F.B.I. agents and employees who point out problems or raise concerns seems to be becoming the rule, not the exception," said Senator Charles E. Grassley, Republican of Iowa. He noted that Robert S. Mueller III, acting director of the bureau, "has said many times that whistle-blower retaliation is unacceptable, yet it looks like some F.B.I. bureaucrats haven't gotten the message."
The F.B.I. has wrestled with accusations from a number of employees who said they were discouraged from voicing concerns, including Coleen Rowley, the Minneapolis agent who protested the handling of the Zacarias Moussaoui terror case in August 2001. In a report disclosed just last week, the inspector general found that complaints by an F.B.I. linguist, Sibel Edmonds, about the bureau's slipshod translation of terrorism intelligence, played a part in her dismissal in 2002.
In Mr. German's case, Senator Patrick J. Leahy of Vermont, the ranking Democrat on the Judiciary Committee, said that "when an F.B.I. agent with a distinguished record questions whether terrorism leads are being followed, the F.B.I. needs to listen." He said Mr. German's complaints "reflect the kind of insularity the 9/11 commission identified as a major management failing in the F.B.I.'s antiterrorism work."
Indeed, Mr. German's assertions echo concerns raised about the F.B.I. in the commission's report.
The commission said that while the bureau had made progress in overhauling counterterrorism operations, its investigation "also found gaps between some of the announced reforms and the reality in the field." One concern was that the F.B.I.'s 56 field offices still retain the power to reallocate agents and resources to local concerns that may diverge from national security.
Mr. German's account of what he considers undue restraint in pursuing terrorism leads may give pause to civil libertarians who have accused the F.B.I. of rushing to judgment and using overly aggressive tactics in some terror cases.
At the same time, however, his assertions raise questions about whether the bureau has fixed some of the bureaucratic problems that stymied terrorism investigations before the Sept. 11 attacks, and his perspective could add grist to the debate over restructuring intelligence operations.
Mr. German, in his letter to lawmakers, cited "a continuing failure in the F.B.I.'s counterterrorism program," which he said was "not the result of a lack of intelligence, but a lack of action."
Officials said Mr. German also complained internally about a second case in the Portland, Ore., area in 2002 in which he said he was blocked from going undercover to pursue a domestic terrorism lead. That case was also thought to center on a militia group suspected of plotting violence.
In the Tampa case, officials said Mr. German complained that F.B.I. officials had mishandled evidence concerning a suspected domestic terrorist group and failed to act for months on his request in early 2002 to conduct an undercover operation. That failure, he said, allowed the investigation to "die on the vine."
While Mr. German would not confirm the location of the investigation, he said in an interview at the office of his Washington lawyer, Lynne Bernabei, that his problems intensified after he complained about the management of the case in September 2002. He said F.B.I. officials whom he would not name backdated documents in the case, falsified evidence and falsely discredited witnesses in an apparent effort to justify their approach to the investigation. He cited institutional inertia, even after Sept. 11.
"Trying to get approval for an operation like this is a bureaucratic nightmare at the F.B.I.," he said.
Mr. German said that beginning in late 2002, he took his concerns to his supervisors at the F.B.I. and to officials at headquarters in Washington, including Mr. Mueller himself, in an e-mail message that he said went unanswered. He also went to the Justice Department's inspector general and, frustrated by what he saw as a languishing investigation, brought his concerns this spring to several members of Congress and the Sept. 11 commission.
In the meantime, Mr. German said, his career at the F.B.I. stalled, despite what he said was an "unblemished" record and an award for his work in the Los Angeles skinhead case.
Soon after raising his complaints about the 2002 terrorism investigation, he was removed from the case. And, he said, F.B.I. officials wrongly accused him of conducting unauthorized travel, stopped using him to train agents in "proactive techniques" and shut him out of important domestic terrorism assignments.
"The phone just stopped ringing, and I became a persona non grata," he said. "Because I wouldn't let this go away, I became the problem."
For now, he has no job and is uncertain about his future.
"My entire career has been ruined, all because I thought I was doing the right thing here," he said.
Correction Tuesday, August 3, 2004
Because of an editing error, an article yesterday about a former F.B.I. agent who complained of retaliation after voicing concerns about the effect of management problems on terror investigations misstated the title of Robert S. Mueller III at the bureau. He is the director, not acting director.