Distracted police station staff failed to notice a man suddenly die in his cell, an inquest was told.
Adam Rice died of an aortic dissection between morning checks at the Elland Road police station on May 12, 2014.
The hearing was told staff had monitored him on CCTV during his detention.
Independent Police Complaints Commission investigator Lindsay Harrison gave evidence at the inquest at Wakefield Coroner’s Court yesterday.
She said: “Staff engaged in casual conversation about non-work related issues.
“While this was happening, Adam was lying in his cell.”
There was “no handover process and staff appeared confused about what they were doing,” she added.
Mr Rice, 46, had been taken to Leeds General Infirmary with a suspected head injury the previous day.
He refused a scan and discharged himself but was arrested for failing to answer bail over an allegation of theft and detained at Elland Road station.
The inquest continues.