Police received a call on its emergency number from a telephone at 2905 North Troy Street, the residence of 21-year-old John Ellis, a deaf-mute, and his parents. The caller told police that a man wanted by the Department was or had been present at that address. Officers Calandra and Kusar responded to the call. They found the front door partially open and saw nobody outside the house. They knocked at the door and announced themselves as police officers and entered the dwelling without a search or arrest warrant. They heard 'scratchy noises' coming from behind a closed kitchen door. A large German shepherd dog emerged. Officer Kusar testified that the dog lunged at him, at which point he fired two shots, killing the animal. P emerged from the bedroom and attempted to approach the animal. With his service revolver still drawn, Officer Kusar motioned P away from the dog and led him to the front of the house. No further search of the premises was conducted. P and his parents filed suit under 42 U.S.C. § 1983 (1976) and the Due Process Clause of the Fourteenth Amendment. Officer Kusar asserted a good faith defense and the City of Chicago asserted that any violation of plaintiffs' civil rights was not the result of official policy or custom. Officer Calandra and Sergeant Holub are police officers employed by the City of Chicago. P called them as witnesses. The court refused to allow P to ask leading questions. During examined neither was hostile or evasive. Ds got the verdict, and Ps appealed.