Elected police commissioners are showing a "worrying" ability to evade rules when sacking chief constables, MPs have warned.
Protections in place that allow police chiefs to fight their corner if they are being forced out appear to be being side-stepped, according to the Home Affairs committee.
It says the early indications are that it is "very easy" for a police and crime commissioner (PCC) to remove a chief constable for reasons of an "insubstantial nature" and even the Home Secretary is powerless to intervene.
MPs warned it was further evidence that the checks and balances on PCCs are "too weak". They were particularly critical of Gwent commissioner Ian Johnston who "persuaded" Chief Constable Carmel Napier to retire earlier this year, which meant the formal process was bypassed.
The committee said the reasons given for the decision were "unsubstantiated by any concrete examples". It also rounded on him for criticising the grilling he received about the move at the hands of Labour MP Chris Ruane, who represents the Vale of Clwyd in North Wales.
"We were disappointed that, shortly after we took evidence from Mr Johnston, he took to Twitter to criticise a member of the committee for asking questions that he believed had been prompted by Gwent MPs, describing the proceedings as 'sad really'," the report said. "Mr Johnson even described Mr Ruane as a 'plant of Gwent MPs'. This disdainful attitude towards scrutiny by Parliament, as well as an indication of a clear over-sensitivity to criticism, from a politician elected by less than 8% of the electorate, who had managed to side-step the statutory arrangements for local scrutiny of his decision to sack the chief constable, is further evidence, if any were needed, that the checks and balances on police and crime commissioners are too weak."
Commissioners remove chief constables by "calling upon" them to resign or retire but they must first give a written explanation of the reasons for the proposal and then consider any response.
Keith Vaz said: "It is worrying that police and crime commissioners seem able to side-step the statutory process for dismissing a chief constable. Police and Crime Panels should make more active use of their powers to scrutinise decisions such as this. We will be returning to this area when we carry out our next major inquiry into Police and Crime Commissioners, towards the end of this year."
Tony Lloyd, chairman of the Association of Police and Crime Commissioners' board, said: "In the vast majority of cases, the relationship between police and crime commissioners and chief constables have developed strongly and purposefully. The appointment and removal of a chief constable is a duty that police and crime commissioners take very seriously. Police and crime commissioners and chief constables work together to decide the direction of travel of a force and police and crime commissioners have a duty to hold chief constables to account for the delivery of the most efficient and effective service for the public.
"Commissioners are mindful that a good working relationship with their chief constable is good for force morale and will contribute to better decision-making... The public elected police and crime commissioners to hold chief constables to account so we welcome measures to improve transparency and enhance the confidence of the public. We will continue to work closely with chief constables to meet the demands of 21st century policing."