Police Powers - PC Parker

Mandy is 15 years old. She was stopped in the street by PC Parker, who was investigating a report of shoplifting at a nearby sweet shop. PC Parker searched Mandy's bag and found several bars of chocolate. He then accompanied Mandy to her home. The house was empty, as Mandy's parents were out at work. PC Parker searched the house and found a DVD player which he thought might be stolen property. He arrested Mandy and took her to the police station, where she was questioned about the DVD player. Her request to contact her parents and a solicitor were refused. Mandy was held in custody until the following afternoon and is to be prosecuted for theft of the DVD player. 

Advise Mandy as to the legality of the actions of the police.

Adapted from English Legal System (4th ed) Elliott & Quinn.