In this scenario, what did the officials involved do incorrectly?
they did not inform the defendants of their rights before questioning them.
they allowed the defendants to contact others involved before questioning them.
they illegally arrested the defendants before questioning them.

in each of these cases, the defendant, while in police custody, was questioned by police officers, detectives, or a prosecuting attorney in a room in which he was cut off from the outside world. none of the defendants was given a full and effective warning of his rights at the outset of the interrogation process. —opinion of the court chief justice warren