The trial of a former Perry middle school principal accused of downloading child pornography on his home computer has been postponed. A judge will review a defense motion to suppress evidence. Arthur Pixler was arrested last October and charged with sexual exploitation of a minor after Perry police searched his home computer. They found pictures of minors in sexual acts. There were no pictures of Perry students found in the computer, and no school property was used. Pixler’s trial was scheduled to begin Tuesday in Dallas County.