Last week, just days before McVeigh was to die in the first federal execution in 38 years, the Justice Department told defense lawyers that the FBI had failed to turn over 3,135 pages of evidence that should have been provided more than three years ago during trial.
Attorney General John Aschcroft delayed the execution until June 11 and ordered an investigation by the department's inspector general.
On Monday, Senior Agent Danny Defenbaugh, the FBI agent in charge of the Oklahoma City bombing investigation, was summoned to Washington to explain how such a foul-up could happen.
In an interview just one day before the revelation, Defenbaugh seemed unaware of the firestorm he was about to ignite saying that unlike Waco and Ruby Ridge, everything had been done right in the McVeigh investigation.
Speaking to CBS affiliate KVTV-Dallas on May 7, Defenbaugh said, "There's been nine or 10 or 11 different reviews up, including a number of congressional reviews. There hasn't been one of the Oklahoma City bombing case, and the reason why is because that was done correctly and properly."
"Every time you hear criticism of the FBI you never hear about the Oklahoma City bombing case," he said.
That changed last week.
Since the 1995 bombing, the FBI had asked field offices five times to forward all materials to the Oklahoma City bureau, where they were being archived. The latest request was made last December.
As materials filtered in earlier this year and were checked against 26 databases of investigative files, officials made a startling discovery some of the papers appeared to be new.
The day after his KVTV interview, according to the Justice Department, Defenbaugh told superiors that he had located a large load of evidence not turned over to the defense. McVeigh's lawyers were informed the same day.
FBI director Louis Freeh and Ashcroft weren't told until Thursday, the Justice Department said.
According to the letter from the Justice Department to the defense team, the evidence includes FBI "302" reports of interviews, as well as photographs, letters and tapes. Some of the material concerns people who "at one time were thought to resemble" the composite sketches of the bombing suspects produced early in the investigation.
The FBI said Monday that none of the documents mentions McVeigh or his accomplice, Terry Nichols, by name. There are three boxes of records from 47 FBI field offices. Los Angeles alone provided 447 documents.
The FBI has been criticized for years for mismanaging information it collects in some of its biggest cases. Former Justice Department Inspector GeneraMichael Bromwich found similar lapses when he investigated other FBI blunders.
"If those problems though have been well known for awhile, the question is why they haven't put systems in place to work around those problems so that problems like this won't emerge, " Bromwich said.
So far, Freeh, who announced a week before the revelations that he would leave his post in June, has had nothing to say. But he's sure to be asked about it when he appears before congress later this week on other business.
There are calls both on Capitol Hill and from others to take a closer look at how the FBI operates. A CBS News Poll found that, while the error is further tarnishing the FBI's image, a majority of the public still believes McVeigh should be executed.
McVeigh was scheduled to die by lethal injection at the federal prison in Terre Haute, Ind., at 7 a.m. CST on May 16. That would have been the first federal death penalty execution administered since 1963.
Ashcroft said he will not impose any further delays. But CBS News legal consultant Andrew Cohen said that the Justice Department decision to delay execution "doesn't preclude McVeigh from asking for even more time."
A defense lawyer said McVeigh has not instructed his defense team to pursue any legal strategy following the FBI's failure to disclose evidence in the Oklahoma City bombing case.
But defense lawyer Rbert Nigh said Sunday, "the facts of the case are now certainly at issue." The withheld documents, he said on "Fox News Sunday," "clearly were required under the legal agreement of the parties to be produced prior to trial, but they were not."
On CBS News' Face The Nation, he added "it's the prosecution that has the ultimate responsibility for making sure that discovery is complied with."
The defense team has just begun reviewing the documents and Nigh said he was not prepared to disclose what was in the material. He did, however, contend that "the fact of the production itself could possibly change the legal outcome of the case."
Although McVeigh has confessed to the bombing to two groups of writers, Nigh said he might reconsider now whether he wants to be executed.
Lawyers for convicted accomplice Terry Nichols aren't waiting: They have asked the Supreme Court to reconsider an appeal. In April the court, without comment, turned down Nichols' request for a new trial.
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