Updated

Prosecutors in the first major terror trial after Sept. 11 were hindered by superiors from presenting some of their most powerful evidence, including testimony from an Al Qaeda (search) leader and video footage showing Usama bin Laden's (search) European operatives casing American landmarks, Justice Department memos show.

The department's terrorism unit "provided no help of any kind in this prosecution," the U.S. Attorney's office in Detroit wrote in one of the memos, which detail bitter divisions between front-line prosecutors and their superiors in Washington.

The Detroit case ended last summer with the convictions, hailed by the Bush administration, of three men who were accused of operating a sleeper terror cell that possessed plans for attacks around the world.

A fourth defendant was acquitted, however, and only two of the four men originally arrested were convicted of terrorism charges. Now the convictions are in jeopardy because of an internal investigation into allegations that defense lawyers were denied evidence that could have helped them.

Whatever the outcome, internal documents obtained by The Associated Press and more than three dozen interviews with current and former officials detail how the differences between Washington and the field office kept important evidence from being shown to jurors.

"We were butting heads vigorously with narrow-shouldered bureaucrats in Washington," Assistant U.S. Attorney Richard Convertino (search) told AP in an interview. He is the lead Detroit prosecutor who is now under investigation in Washington.

"There was a series of evidence, pieces of evidence, that we wanted to get into our trial that we were unable to do. Things that would have strengthened the case immeasurably, and made the case much stronger, exponentially," Convertino said.

For instance, the FBI had learned before the trial that Ibn al-Shaykh al-Libi, Al Qaeda's training camp chief, told interrogators after his capture that bin Laden had authorized an attack on the Incirlik air base in Turkey where U.S. military jets flew missions over Iraq (search) for the past decade, Convertino said.

The interrogation was deemed important because the FBI (search) found in the Detroit terror cell's apartment sketches of the same Turkish base, including flight patterns of U.S. jets. Al-Libi's testimony would have connected the Detroit defendants to a planned Al Qaeda attack, Convertino said.

But al-Libi was "spirited off from Afghanistan (search) to Egypt and we were not able to interview him or use him as a witness," Convertino said.

Turkish authorities recently told the AP that their own evidence shows bin Laden personally authorized an attack on the base but later abandoned the plan because security was heightened. U.S. officials raised security at Incirlik within days of the Detroit discovery, Air Force officials say.

Justice officials declined comment, citing a partial gag order the judge has imposed in the Detroit case. But internal memos show Washington frequently criticized the Detroit prosecutors as "not adequately supervised" and providing "minimal" cooperation.

In another example, prosecutors obtained a videotape showing that an Al Qaeda cell broken up by Spanish authorities in 2002 in Madrid had video surveillance of the same American landmarks that were found on a video with the Detroit cell.

The Spanish and Detroit tapes, obtained by the AP, show surveillance of casinos in Las Vegas, various landmarks in New York, including the World Trade Center (search), and Disneyland in California. Both tapes showed nearly identical footage of security, information on how cars could access the landmarks, and other footage that could be useful for staging an attack.

The Spanish tape, which dated to 1997, included "footage of several potential targets of Al Qaeda" and was later carried via courier to Al Qaeda leaders in Afghanistan, according to Spanish documents provided to U.S. authorities.

Prosecutors obtained the Spanish footage from a Justice Department terrorism expert just weeks before the trial and even created several slides that would identify for jurors the numerous similarities between the Detroit and Madrid videos.

"The Detroit cell and the Spanish tapes identify three identical targets for surveillance," said one of the slides, which jurors never saw. A different slide said the two tapes follow the Al Qaeda training manual because "surveillance is inserted into seemingly innocent tourist videos."

The Spanish tapes show an Al Qaeda operative panning the World Trade Center and shooting the skyline that the eventual Sept. 11 hijackers used to fly their planes into the towers. The operative even puts his arm around a famous statute outside the towers as well as around the statue of a bull near Wall Street.

Both tapes have extensive footage of Hollywood, Disneyland and Las Vegas casinos. "Let's go to the hotel since we finished filming the casinos and we made $100,000 tonight," the Spanish operative says on one of the tapes, according to transcripts made by Spanish authorities.

Prosecutors were told by superiors they could not introduce the Spanish tape unless they went through a lengthy bureaucratic process, known as the Letters Rogatory, that establishes chain of custody for foreign evidence.

The process would take months to complete through diplomatic channels. With just weeks before the trial and no willingness in Washington to delay the trial, prosecutors abandoned the evidence, Convertino said. That meant the Detroit tape was introduced at trial in isolation, with jurors given no chance to see how closely it resembled a tape U.S. officials knew had reached Al Qaeda's leadership.

Some disputes reached high into the Justice Department.

The FBI had identified three witnesses — a landlord, a Jordanian informant and a prison inmate — who linked the Detroit cell members to the FBI's No. 27 listed Al Qaeda figure, Nabil al-Marabh. The prosecutors wanted to charge al-Marabh as a fifth defendant.

But Deputy Assistant Attorney General David Nahmias balked. "My understanding is that the only connection between al-Marabh and your case was an apparent misidentification by a landlord," Nahmias wrote.

A few months later, the government deported al-Marabh to freedom in his home country of Syria.

Other memos show the chief of the elite organized crime strike force in Detroit, Assistant U.S. Attorney Keith Corbett, challenged the judgment of Justice's terrorism chief, Barry Sabin.

"I see no reason to listen to petty bureaucratic complaints by people who will not and could not try the case," Corbett wrote. "Sorry if this response seems impolite, but I have had it with Barry Sabin."

When Washington evaluated the Detroit office as uncooperative after the trial, Detroit responded with a strong retort.

The lone Justice lawyer sent from Washington to help told his Detroit colleagues "he had no intention of participating in the trial" and refused to assist when an urgent issue arose involving a witness and the State Department, the Detroit office wrote.

The Washington lawyer "spent the same 10 (trial) weeks in a hotel at taxpayers' expense when he was not playing basketball in the evenings," the memo stated.