The Police Investigations and Review Commissioner (Pirc) has been instructed by the Crown Office and Procurator Fiscal Service (COPFS) to probe the circumstances leading up to the man’s death.
It follows the discovery of a body at a residential property in Stevenston, North Ayrshire, on Sunday, September 18.
A spokesman for the Pirc said: “The investigation will focus on the deceased’s interaction with officers from Police Scotland prior to his death.
“A report on the commissioner’s findings will be submitted to the COPFS in due course.”
A Police Scotland spokesman confirmed that the investigation was in relation to police contact with the man on Saturday, September 17.