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."
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