FBI Director Robert Mueller sought on Wednesday to dispel any perception among Americans that the bureau and the Justice Department let bankers go free after they helped bring about the U.S. financial crisis.
The complexity of the crisis made it difficult to identify what crimes might have occurred and to explain to Americans why there was a scarcity of prosecutions on Wall Street, Mueller told reporters in response to questions about the crisis.
Mueller was speaking in a rare interview 12 years into the job and just weeks before his Sept. 4 departure.
"I would say that's a misperception. There were a number of contributing factors to the crash in 2008, and if you look at the statistics in terms of persons we've investigated and prosecuted, there are a number that are out there, and investigations are ongoing," said the 69-year-old former prosecutor and U.S. Marine.
"Often it's very difficult to put it all together and paint a picture that is persuasive when you have such disparate contributing factors to a particular crisis," he added, "but where we've found the evidence and we've followed the evidence, I think we have a pretty good track record."
The FBI granted the Wednesday interview on condition it not be reported until late on Thursday, to accommodate other interviews.
Mueller did not mention specific recent cases but said comparisons to earlier sweeps of white-collar crime, such as the savings-and-loan crisis that began in the late 1980s, were unfair. Back then, he said, "The cases were relatively easy to identify and were clear frauds."
While he called insider-trading cases an "offshoot" from the financial crisis, he said U.S. investigators should get credit for bringing those, too.
Mueller became FBI director a week before the hijacked plane attacks of Sept. 11, 2001, on the World Trade Center in New York and the Pentagon, a calamity that forced the bureau to shift radically its priorities and capabilities.
He will leave behind a very different FBI. More than half the agents began work there after the Sept. 11 strikes, and the bureau's first priority - unquestioned in Washington - is to prevent a similar attack.
"I did not expect I'd be spending my time in preventing terrorist attacks," Mueller said. He had spent his career prosecuting crimes - including local murders in Washington - after they occurred, not preventing them.
Mueller's 12-year stint makes him the second longest-serving director in FBI history after J. Edgar Hoover.
"In the last 12 years, I think the American public has expected us to, yes, clean up the white-collar criminal activity, yes, handle public corruption, but most particularly to not allow another Sept. 11 attack," he told reporters, sitting in a conference room at the FBI's J. Edgar Hoover Building in Washington.
With 36,000 employees, the FBI is the largest U.S. investigative agency and the closest thing the country has to a national police force. Its investigations cover not only counterterrorism but organized crime, financial fraud, cybercrime and more.
QUESTIONS ABOUT BOSTON, FORT HOOD
Mueller would not address several of the subjects reporters raised. He repeatedly declined to comment on the U.S. pursuit of former National Security Agency contractor Edward Snowden, charged under espionage laws for leaking secrets to newspapers.
Despite praise from lawmakers for the lack of another major attack on U.S. soil on his watch, Mueller said part of the success was luck. He also said he still wonders if more could have been done to prevent April's Boston Marathon bombing and the shooting in Fort Hood, Texas, in 2009.
The two attacks share a pattern of "individuals acting pretty much on their own, without ties to a formalized terrorist group, not orchestrated overseas," he said, and the model would probably be replicated by others.
A government-ordered review of the Fort Hood shooting said the FBI had no specific knowledge that Major Nidal Hasan was planning the attack, but that the bureau should have interviewed him because it was in possession of emails Hasan had sent to a militant Muslim cleric.
A jury is weighing whether to convict Hasan, who is accused of killing 13 and wounding more than 30. His trial began last month.
An official review of the Boston bombing, in which two bombs exploded, killing three people and wounding about 260, has not been released.
After nearly an entire adult career in government, Mueller said he planned to spend time giving speeches, teaching and conducting private investigations. He said he had yet to decide whether to join a firm or start his own.