Former Home Secretary Charles Clarke has warned that plans to overhaul how police forces are held accountable are 'very dangerous to society' and will 'destroy' efforts to tackle crime.

The comments by one of New Labour's former leading lights threaten to undermine government attempts to introduce directly elected representatives on to the boards of police authorities, the regional bodies which determine how each of the country's forces tackles crime.

They come as a survey of senior police officers reveals that almost as many believe such a move will make fighting crime harder. The Local Government Association, the cross-party organisation representing councils in England, surveyed all 212 senior police officers in charge of local policing. Of the 65 who responded, 79 per cent said the government's plans will make their jobs more difficult.

In a letter to Sir Jeremy Beecham, vice-chairman of the association, seen by The Observer, Clarke warned that the creation of the new 'crime and policing representatives' will result in a politicisation of the police.

The representatives will be elected in local elections solely on their manifestos for cutting crime. Concerns have already been expressed that the move will result in extremist parties such as the BNP securing positions on police authorities. Clarke said that he could envisage a situation where the representatives are elected on single-platform manifestos such as to 'arm all police' or to 'prevent officers taking certain forms of action in industrial disputes'.

He warned that this will create tensions for forces which will have to make an 'invidious choice' between ignoring the views of a directly elected politician or 'implementing a policy that they believed to be operationally quite wrong'.