Four separate cases involving similar fact situations were consolidated because they presented the same constitutional question. In each case, police officers, detectives, or prosecuting attorneys took a defendant into custody and interrogated him in a police station to obtain a confession. In none of these cases did the officials fully and effectively advise the defendant of his rights at the outset of the interrogation. The interrogations produced oral admissions of guilt from each defendant, as well as signed statements from three of them, which were used to convict them at their trials. The defendants appealed, arguing that the officials should have warned them of their constitutional rights and the consequences of waiving them before the questioning began. It was contended that to permit any statements obtained without such a warning violated their Fifth Amendment privilege against self-incrimination. Were the defendants’ constitutional rights violated? Discuss.