Campaigners are celebrating a landmark High Court victory over Barnet Council after controversial parking charge increases spearheaded by Cllr Brian Coleman were deemed unlawful.

East Finchley resident David Attfield, 46, brought a two-year battle against the council’s controlled parking zone (CPZ) charges to the Royal Courts of Justice earlier this month.

Yesterday, judge Mrs Justice Lang ruled that the council had acted unlawfully by hiking parking charges to pay for other transport projects in April 2011.

Mr Attfield insists the ruling will have national ramifications - if Barnet Council had won, local councils across the country would have found themselves with sweeping powers to use parking as a revenue-raising service.

He said: “It’s an important judgement. There was no need for the parking charges, the council simply saw the CPZ residents as an easy target to make £1.5million and that has been found to be unlawful.

“Local authorities [across the country] will be very, very careful in the future about the way they set parking charges.”

The father-of-two, who lives within a CPZ in Summerlee Avenue, has been forced to pay an extra £60 a year for a residential parking permit, as well as an extra £3 each time a visitor parks, since the changes were driven through by Cllr Coleman, then cabinet member for environment, in 2011.

The changes increased the price of residential permits in all Barnet CPZs from £40 to £100 annually and increased visitor permits from £1 to £4.

Under the Road Traffic Regulation Act 1984, Martin Westgate, QC, representing Mr Attfield in the High Court, argued that the council could only raise parking charges for “traffic management” purposes in the CPZ, not to simply increase revenue elsewhere.

The council insisted it was well within its rights under the 1984 Act to hike parking charges to enhance its highways budget.

But Mrs Justice Lang sided with Mr Attfield, concluding in her ruling that the 1984 Act is “not a fiscal measure”.

Barnet Council leader, Cllr Richard Cornelius, said the council’s “pricing and spending are very much in line with other London boroughs”.

He said: “With that in mind I don’t think we have any alternative but to look to appeal this decision.

“That said it is fairly clear that the council raised the price of parking permits, after five years of a price freeze, too abruptly and rather charmlessly. I will make sure that doesn’t happen again.”

It is understood that in light of the High Court judgement every Barnet resident affected by the parking charge hikes will have the cost of the unlawful increase refunded, but not before the conclusion of any potential appeal hearing.

Parking charges in CPZs will also automatically revert to the level set prior to the unlawful hike - unless Barnet Council wishes to alter the original price - pending the result of any appeal case.

Mr Attfield urged the council to abandon thoughts of an appeal, explaining: “They need to understand that the power they are seeking is not a power that any other local authority is arguing for. There is no real justification for them to appeal this.”