There is a real possibility of extremists winning seats on police authorities if ministers go ahead with plans for direct elections, the country's senior police chiefs have said.

The Association of Chief Police Officers (ACPO) said that rather than holding elections to increase politicians' influence over local policing, “the public needs to be protected from political control of the service.”

Senior officers are already extremely concerned at the way in which Boris Johnson, the Conservative Mayor of London, forced the resignation of Sir Ian Blair as Metropolitan Police Commissioner.

In a stark warning to politicians, the ACPO cautioned against "tinkering" with the operational independence of chief constables.

The Times revealed today that the far-right British National Party is confident of winning seats on police authorities when elections are introduced.

All the main political parties favour increased democratic accountability of policing, either by electing members of authorities or local police commissioners.

Simon Darby, deputy leader of the BNP, said that he believed his party's “no-nonsense” approach to crime would win it representation and influence over policing.

A BNP push at police authority elections could benefit from the impact of rising crime in a recession and a low turnout at the polls. The party won its latest council seat in Lincolnshire last week on a 22 per cent turnout.

In its official response to the Home Office Green Paper on the future of policing, the ACPO said the idea of directly elected police authorities was fraught with danger.

"The election of someone on a single issue or on an extremist ticket is a real possibility," the document said.

If that occurred, senior officers say, the current tripartite balance between forces, central Government and police authorities flies out of the window.

The ACPO said that if the plan went ahead, nothing would stand between a Chief Constable and local politics. It said that there were clear risks in giving politicians the ability to sack chiefs, withhold bonuses or influence operations.

The policy paper said police were concerned that there would be less representation for ethnic minority communities and that there would be the potential for conflict if a police authority was under different political control from a local council.

The ACPO argued that the current three-way arrangement has stood the test of time, crises and challenge.

It said: "They are a balancing mechanism that ensures that the Government of the day has influence over the direction of policing without controlling its delivery. They also ensure that local communities have a voice on priorities and performance expectations.

"These arrangements further ensure that Chief Constables are accountable at both a national and local level but retain the operational independence to act in the public interest and avoid being politicised or constrained by single-issue politics. Changes to this tripartite arrangement would require legislation but Government should be cautious when considering tinkering with this arrangement."

The Green Paper does not specify what proportion of seats on a police authority would be elected. The Liberal Democrats want two thirds of members to stand for election. The Conservatives have proposed elected commissioners for each force area.

However, opposition to the ideas of all three parties is growing and the Local Government Association said that elections would cost the taxpayer more than £30 million.

Margaret Eaton, the chairman of the association, said: ”Extra elections for police representatives would be a pointless waste of taxpayers' hard earned money. At a time when the whole country is having to tighten its belt and the Government's cupboard is bare, here they are suggesting spending tens of millions on elections that are completely unnecessary.

“This money could be spent putting hundreds of extra police officers on our streets, at the frontline of the fight against crime. It's vital local people have a say in how their area is policed, but introducing these elections is absurd."

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