Appellate judges questioned Monday whether a judge erred in barring some testimony from the trial that convicted a former Bush administration official of lying about his relationship with Republican lobbyist Jack Abramoff.

David Safavian, former chief of staff at the General Services Administration, was convicted last June of false statements and obstruction and sentenced to 18 months in prison in the first trial to emerge from the Abramoff scandal. Safavian, who later worked in the White House as chief federal procurement officer, is free pending the outcome of his appeal.

Safavian, former Deputy Interior Secretary Steven Griles and former Rep. Bob Ney, R-Ohio, are the highest-ranking officials sentenced to prison so far in the corruption probe. Abramoff and eight others, including lobbyists, former congressional aides and another former Interior official, also have pleaded guilty. The scandal is credited with contributing to the shift of control in Congress last November from Republicans to Democrats.

A jury found that Savafian, a friend and former co-worker of Abramoff's, had hidden details of his relationship with the powerful lobbyist from a General Services Administration ethics officer, the GSA inspector general and the Senate Indian Affairs Committee and had obstructed an investigation by the inspector general.

Safavian obtained an opinion from the ethics officer that he could go on an expensive Abramoff-organized golfing trip to Scotland with Ney and Abramoff. Safavian told the ethics officer that Abramoff did no business with GSA although e-mails showed that at the time Safavian was advising Abramoff on how to obtain two GSA-controlled properties, including the historic Old Post Office in downtown Washington, that the lobbyist wanted.

Laurence S. Robbins, Safavian's lawyer, argued that District Judge Paul Friedman barred key supporting testimony for Safavian's defense that he used the "doing business" phrase "not as laymen do but as a government contract professional does," that is, holding or bidding on a contract. The two properties had not reached that stage yet. Friedman barred a defense expert from testifying that contracting professionals use the term the way Safavian claimed he did. Friedman said such testimony might confuse the jury.

"I don't know how that's not admissible," said Judge Harry T. Edwards as he and fellow Judges A. Raymond Randolph and Judith W. Rogers of the U.S. Court of Appeals from the District of Columbia all probed the basis for Friedman's ruling. Edwards and Rogers were appointed by Democratic presidents; Randolph by a Republican.

Justice Department lawyer Nathaniel Edmonds countered that at the time Safavian was describing Abramoff's work, not his own, and Abramoff was a lobbyist, not a procurement specialist. Edmonds added that most of Safavian's experience was in lobbying rather than procurement. Besides, Edmonds said Safavian made other false statements about who was paying for the trip and its duration.