The inquiry is a mandatory inquiry under Section 2(4) of the Inquiries into Fatal Accidents and Sudden Deaths etc. (Scotland) Act 2016 as at the time of his death Mr McKenzie was in custody at HMYOI Polmont.

A preliminary hearing will be held on 19 December at Stirling Sheriff Court.

Procurator fiscal Andy Shanks, who leads on fatalities investigations for COPFS, said: “The lord advocate considers that the death of Jack McKenzie occurred while in legal custody and as such a Fatal Accident Inquiry is mandatory.

“The lodging of the first notice enables FAI proceedings to commence under the direction of the sheriff.”