Its not unusual to charge without interview in these circumstances, particullarly in an assault case such as this as there there would already be sufficient evidence to charge anyway. The protocol is to still ask the relevant questions through the cell door while the evidenctial tapes are recording so that inferences could be allowed in court should the accused answer 'no-comment' etc, however, if the mental health aspect was considered along with violence and further risk then this would be acceptable to just charge as in this case.
Kim, how do you know he was beaten up in the cells if you have not spoken to him? Also, you say this behaviour was out of character but I am mindful he is on a suspended sentence for violence alread