Nick Gargan was appointed as chief constable of Avon and Somerset Police in March last year.
Mr Gargan started his career with Leicestershire Constabulary in 1988 after completing a degree in French and politics at the University of Leicester.
He worked extensively on the investigation into the death of Diana, Princess of Wales.
A spokesman for the force said: "The matter has been referred to the IPCC by the Police and Crime Commissioner. It is not appropriate for us to comment any further."
More top news
The young royal says he was reluctant to take on the responsibilities of his title, but loyalty to the Queen helped him "work out a role".
A rather cloudy morning will clear to sunny intervals and showers this afternoon.
Meng Meng and Jiao Qing arrive in their new home after being loaned to Berlin Zoo for 15 years as "diplomatic envoys" from China.