Police sometimes tell a child that he must tell the truth. Sometimes police describe the evidence against the suspect before reciting the Miranda warning; this puts pressure on the young suspect to waive his right to silence so he can respond to the evidence.
More often, interrogators develop a relationship of trust with the suspect. They tell him this is his opportunity to tell the truth. Police sometimes ask booking questions—the juvenile’s name, age, grade in school, etc.—to get him talking and so to reduce the chance he’ll invoke his right to silence when they tell him of it. Sometimes police discount the warning as a formality.
Feld gives an example of a police officer’s emphasizing the value of talking while minimizing the importance of the Miranda warning:
“I just started investigating yesterday, and what I’ve learned over the years… there’s always two sides to every story and this is your opportunity to give your side of the story. Under law, I have to advise you of your Miranda, your legal rights, per Miranda, and I’ll read those now.”
According to Feld, police have a conflict of interest when they give the Miranda warnings to either an adult or a juvenile. Giving the warning places police in an advisory capacity. But police have interests adverse to suspects; they would much rather see a suspect waive his rights than invoke them.