ALEXANDRIA, VA. - The federal judge overseeing the death penalty trial of confessed Al-Qaida conspirator Zacarias Moussaoui ordered a court inquiry today to determine whether a government lawyer's coaching of federal air security witnesses warrants dismissal of the case.

Outraged that her trial conduct order had been breached, U.S. District Judge Leonie Brinkema recessed the proceedings Monday and ordered a hearing to examine the extent that testimony of Federal Aviation Administration officials has been tainted.

In e-mails over the last week, lawyer Carla Martin of the Transportation Security Administration sent the seven present and former FAA officials a transcript of the trial's first day. She and most of the seven are expected to testify. She advised them that a prosecutor's opening statement "has created a credibility gap that the defense can drive a truck through."

Martin suggested ways in which the FAA witnesses should testify to minimize the damage.

"In all the years I've been on the bench, I've never seen such an egregious violation of the court's rules on witnesses," Brinkema declared. In February, Brinkema issued an order barring witnesses from following the trial proceedings. It prohibited them from reading trial transcripts.

The judge sent the jury home until Wednesday so she can question Martin and the FAA witnesses and weigh remedies. Defense lawyers called for a mistrial or the exclusion of FAA witnesses planning to testify for the government.

FAA testimony is critical

FAA officials' testimony is critical to both sides. Prosecutor David Novak told the judge that the government's three FAA witnesses represent "nearly half of this case."

Prosecutors contend that the agency could have taken steps, such as banning short-bladed knives, to stop the terror attacks if Moussaoui had told interrogators that he was involved in a suicide hijacking plot when he was arrested in the Twin Cities in August 2001. Defense lawyers contend that the FAA and other government agencies knew more than Moussaoui did about the suicide hijacking threat and failed to stop it.

In her initial, March 7 e-mails to two senior FAA security officials, Martin said lead prosecutor Robert Spencer's opening statement contained "more than a few errors."

The next day, she urged FAA witnesses slated to testify for the government to acknowledge that agency X-ray machines could not identify all short-bladed knives like those used by the Sept. 11 hijackers, so they would not appear to be concealing the limitation. She urged Lynne Osmus, assistant FAA administrator for security, to stress that the agency's "multilayered system of aviation security" would have "thwarted the attacks."

The revelations of coaching raise serious issues in the case because "you can't unring the bell ... you can't unprepare people," said Stephen Saltzburg, a professor of criminal procedure at the George Washington University law school.

He said "there are mistakes in every case," and he doubts that Brinkema will throw out the only U.S. criminal prosecution stemming from the Sept. 11 terror attacks. But, he said, "if she concludes that there's no way to remedy this, that they prepared themselves too much ... then the government's in big trouble."

Martin advised the FAA officials that she got the trial transcripts from "my friends" -- lawyers for American Airlines and United Airlines, whose planes were seized on Sept. 11.

In a memo to the judge late Monday, defense lawyers contended that Martin "clearly realized that what she was doing was unethical and improper," because she "told Osmus not to respond to the e-mail."

Prosecutors learned of Martin's coaching Friday, gathered the e-mails and notified the judge and defense attorneys in separate letters Monday. In their letter to Brinkema, prosecutors called Martin's conduct "reprehensible."

Brinkema said prosecutors deserve "great credit" for coming forward with evidence of the misconduct.

Prosecutors urged the judge to review Martin's e-mails privately before deciding "whether they must be produced to defense counsel." They said they had turned over to the defense one Martin e-mail that generated a response from Osmus.