Its the Judge and Jury who decide guilt or innocence not the Police.

Often people think that its the police who decide whether they have committed a crime. If they confess to the crime they think thats it, theres nothing more to be done. Firstly sometimes people dont know what they are actually confessing to. This can be so in complex cases. Obviously if its an assault case its more straight forward. In fact the place that determines guilt or innocence is the Court. They also determine what someone has actually done and importantly they determine how the matter is to be sorted out i.e. what sort of punishment will be handed out. The power of the Court is illustrated by the fact that a person can be discharged by the court without a conviction even when they have committed the offence.