Devon and Cornwall Police has been referred to a watchdog after footage emerged showing a man telling officers 'I can't breathe' while being detained.
They're the same words uttered by George Floyd, whose killing has sparked global protests.
The video - released by the family of Simeon Francis - was taken 10 months before he died in custody at Torquay police station following a separate arrest on May 20.
Mr Francis' family has released the video claiming the officers used excessive force.
Devon and Cornwall Police has referred itself to the Independent Office of Police Conduct (IOPC) over the footage.
A preliminary post-mortem has been held, which did not identify a cause of death for Mr Francis.