The trial is due to start of a man accused of murdering Met Police sergeant Matt Ratana, who was shot inside Croydon police station in 2020.
Louis De Zoysa, from Banstead, Surrey, pleaded not guilty to the charge in April during a hearing at Northampton Crown Court.
The 25-year-old held up a whiteboard with not guilty written on it during the previous hearing, to enter his plea via a video-link to a hospital.
Mr Ratana, 54, died after suffering a fatal wound to the chest at Croydon custody centre in south London on September 25 2020.
De Zoysa, who appeared at the previous video-link hearing in a wheelchair and with his right arm in a sling, also wrote on a whiteboard to confirm his name and date of birth.
Prosecutors allege Mr Ratana was shot while De Zoysa was handcuffed, during an incident in which he also sustained a gunshot wound.
De Zoysa’s jury trial, which is expected to last for around three weeks, is due to open this week before High Court judge Mr Justice Johnson, sitting in Northampton.
The case is being prosecuted by Duncan Penny KC, with Imran Khan KC appearing on behalf of the defendant.
