What if the officer does not read Miranda rights to someone during an arrest?

Miranda rights are rights set up by the Courts so that people in custody are not unduly pressured into giving evidence to the police during interrogation. If the police did not read Miranda to the Defendant, and the police ask the Defendant questions while he is in custody, the Defendant would have a good issue at a hearing to suppress the evidence given to the State during the questioning. If evidence gathered prior to being in custody or is not related to questioning, the State would still be able to use the evidence despite Miranda not being read. For example, if the defendant starts talking to the police in the police cruiser on the way to the police station without being asked questions, the statements will probably not be suppressed as a violation of Miranda.