Tam was scheduled to go on trial on July 31, 1978, but the trial was delayed while a change of venue was being contemplated. Tam's trial began on August 21, and he was convicted on five murder counts and eleven assault counts on September 5, 1978. Attorneys for the defendant made several motions to move the trial venue, sequester the jury, and ban reporters from the courtroom, none of which were granted. During his trial, Tam testified he had deliberately aimed his shotgun away from diners and only participated in the shooting under duress. However, Chester Yu testified that Tam was "very happy" after the shooting and recalled hearing Tam say he "wanted to shoot more people", and Tam was recorded by Robert Woo, threatening the life of a suspected police informant.