Newport West MP Paul Flynn says the row over the forcing out of the former Gwent Chief Constable by the force's Police and Crime Commissioner shows "it is the system that is wrong - it's going to happen elsewhere too."
He said the problem is "two people thought they were running the police force".
Ms Napier has called on the UK government to consider whether the independence of operational policing could be compromised by the power given to PCCs.
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Wintry showers to continue through the weekend and warnings of gales
Exclusive figures given to ITV Cymru Wales show a steep rise in the number of people seeking advice for steroid use.
Cold, breezy and generally cloudy at first with further wintry outbreaks on the hills