Border Patrol Agents Brian Brown and Mike Van Edwards arrested Marnie Burt (defendant) for transporting illegal aliens. Burt informed the agents that she was aware of plans to transport a large number of illegal aliens the following weekend. The agents agreed not to seek prosecution, and Burt agreed to return the following day to provide more information about the upcoming plan. The next day, May 23, Agent George Scott interviewed Burt. According to Burt, Scott informed Burt that if she was working to gather information for the agents, she would not be doing anything illegal. According to Scott, he informed Burt not to do anything illegal and to contact the agents with any information she gathered. On May 28, Burt was arrested again while transporting illegal aliens. Burt claimed that she was working for Van Edwards. After learning of Burt’s arrest, Scott destroyed his notes from the May 23 interview. Burt was charged with transporting illegal aliens and conspiracy to transport illegal aliens. Burt requested a jury instruction on the defense of public authority. The trial court refused the jury instruction, and Burt was convicted on both charges. Burt moved for a new trial, but the motion was denied. Burt appealed on the ground that the trial court erred in failing to give the jury instruction on the public authority defense.