A Conservative candidate for a key marginal seat was spared prison yesterday after a sustained campaign of harassment against his rivals.

Ian Oakley, 31, who had hoped to become MP for Watford, was given an 18-week suspended sentence by St Albans Magistrates' Court after slashing tyres, sending poison-pen letters and making silent phone calls to his Liberal Democrat opponents over a period of almost two years.

He had pleaded guilty at an earlier hearing to five charges of criminal damage and two counts of harassment, and had asked for another 68 offences to be taken into account.

Oakley, of West Drayton, West London, was selected as Conservative candidate for Watford in 2006. Between August of that year and March this year Sal Brinton, the Liberal Democrat candidate, received silent phone calls. Gay magazines and letters addressed to “Sal Bitchton” were sent to her workplace.

Other members and supporters of the local Lib Dems were the victims of graffiti and vandalism during the campaign, which Donna Rayner, for the prosecution, said was motivated by “a desire to change the political landscape in Watford”.

Sentencing Oakley, Barry Northrop, the chairman of the bench, described some of the defendant's behaviour as vile and said that it had been a deliberate attempt to “subvert the democratic process”. Oakley's actions, he said, had made some of the victims too scared to exercise their democratic right to vote.

In addition to his suspended jail term, Oakley was ordered to pay compensation to three victims whose tyres had been slashed and prosecution costs of £70.

Speaking after the hearing, Ms Brinton called for an apology from the Conservative Party. “Many of the people who Oakley targeted felt that we wanted to ensure that it never happens again, that a clear message is sent that you cannot subvert the democratic process.

“I still ask the Conservatives to have an inquiry into how they say they knew nothing about this, and what their systems were for this to have been able to take place.

“The silence has been deafening.”

Last night Hillingdon Council, in West London, where Oakley remained a councillor until yesterday, said that he would be standing down with immediate effect. “The council takes any cases of harassment or criminal damage very seriously, and in particular the distress caused to the victims,” a spokesman said. “This sentence sends a strong message to all those in public office about the behaviour expected of them.”

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