Complex sentence: On arrival at the police station he was "partially dragged and partially carried," handcuffed and unconscious, from a police van and then placed on the floor of the custody suite while officers chatted between themselves and speculated that he was faking illness.
Split into simpler sentences: On arrival at the police station Alder was "partially dragged and partially carried," handcuffed and unconscious, from a police van and placed on the floor of the custody suite. Officers chatted between themselves and speculated that he was faking illness.