David Safavian (defendant) was the chief of staff of the General Services Administration (GSA). While holding this position, Safavian’s close friend, Jack Abramoff, requested information regarding two properties controlled by GSA: White Oak in Maryland and the Old Post Office in Washington, D.C. Safavian provided Abramoff with internal GSA information and attempted to assist Abramoff in developing these properties. Abramoff and Safavian’s efforts did not succeed, and the properties remained under GSA’s control. During these discussions, Abramoff invited Safavian on a trip to Scotland and London and chartered a plane to transport them. Safavian sought advice from GSA’s general counsel about whether he could accept free air travel as a gift. In his request, Safavian stated that he would be paying for his own accommodations, meals, and golfing fees and that Abramoff had no business before GSA. Based on this information, a GSA ethics officer advised Safavian that he could accept the transportation as a gift. Prior to departing, Safavian paid Abramoff $3,100 to cover the costs of the trip. Subsequently, GSA agent Gregory Rowe began investigating the trip. Safavian told Rowe that he paid for his trip, including airfare, and stated that Abramoff did not have business before GSA. Safavian omitted mention of Abramoff’s interest in White Oak and the Old Post Office. A Senate committee later began investigating Abramoff and requested that Safavian produce all records relating to the trip. Safavian informed the committee that he had paid for the cost of the trip and that Abramoff had no business before GSA at the time. Safavian was indicted for falsifying and concealing material facts in violation of 18 U.S.C. § 1001(a)(1) and obstruction of justice in violation of 18 U.S.C § 1505. At trial, Safavian contended that it was reasonable for him to believe that his $3,100 check would cover the cost of the trip, notwithstanding the trip’s lavish nature. Safavian also attempted to introduce expert testimony asserting that among government-contract professionals, doing business with an agency involves having a contract with that agency. The district court did not permit Safavian to present the expert testimony. Safavian was convicted on all counts. Safavian appealed.