Poised to convene its first hard-hitting hearings in January, the federal commission investigating the 9/11 attacks continues to be at odds with the White House over access to key information and witnesses. Two government sources tell TIME that National Security Adviser Condoleezza Rice is arguing over ground rules for her appearance in part because she does not want to testify under oath or, according to one source, in public. While national security advisers are presidential staff and generally don’t have to appear before Congress, the commission argues that its jurisdiction is broader—and it's been requiring fact witnesses in its massive investigation to testify under oath. The exception: it may not seek to swear in President Bush, Vice President Cheney, Bill Clinton or Al Gore...

With such high-profile testimony in the offing...commission chairman...Tom Kean [told] reporters...to expect major revelations from the investigative hearings expected to begin in late January. He also suggested that the 9/11 attacks might have been prevented if...government agencies had done their jobs. As for senior officials like Rice or her predecessor...Sandy Berger, and their bosses, Kean said the commission was still studying whether they share the blame. Rice could face tough questioning. One Republican commissioner says a comment by Rice last year—that no one “could have predicted that they would try to use a…hijacked airplane as a missile" was...unfortunate... [because there were] years of intelligence about Al Qaeda's interest in airplane attacks.

Whether she signs up willingly to testify now is still an open question. But the commission wants to hear from her. Said Democratic commissioner Tim Roemer: "The Presidents and Vice Presidents and national security advisers in both administrations should appear." Spokesmen for Rice and the commission had no comment...but a senior Rice aide insisted that "Dr. Rice and the White House continue to work amiably with the commission, consistent with the President's desire to make staff available in accordance with his ability to fight the war on terrorism."