This chapter describes Sections 34 to 51, which make up Part IV of the Police and Criminal Evidence Act (PACE) 1984. Part IV sets out the conditions under which a person can be held in police detention and when they must be released, the role and responsibilities of the custody officer, and a timetable within which decisions relating to detention and charge must be made. It also talks about a person in police detention for the purposes of PACE if taken to a police station following arrest or is arrested at the police station. The chapter examines how a person is to be treated as under arrest for an offence where they return to a police station to answer bail. It cites Section 34(1), which specifies that a person arrested for an offence will not be kept in police detention except in accordance with the provisions of PACE.