An inquest into the death of a man who died an hour after collapsing in police custody will focus on the 15 hours following his arrest, a coroner said.
Leroy Junior Medford, 43, was taken to hospital after being arrested in Reading on 1 April but was discharged the same day.
He was found unresponsive in his cell at about 04:00 BST the next day before being declared dead in hospital an hour later.
The inquest will take place on 10 June.
Mr Medford, who suffered from diabetes, was arrested by Thames Valley Police on suspicion of assault and a drugs offence.
He was taken to nearby Loddon Valley Police Station but officers became concerned for his welfare and he was taken to the Royal Berkshire Hospital for a check-up.
Mr Medford’s sister Marilyn Medford-Hawkins attended the pre-inquest hearing at Reading Town Hall on Tuesday and said: “If anything like this happens, where someone is in custody and it results in their death, you need to find out what happened.”
Coroner Heidi Connor will lead the “emotive” jury inquest at Reading Town Hall, which is expected to last three weeks.