Dublin’s most persistent parking offender has been identified after a four-year analysis of registration numbers found one car had been clamped 63 times.

The driver, whose name has not been revealed, will have clocked up at least €5,000 in clamping release fees, but the city’s parking appeals officer, Bill Keilthy, said the charges appear to have lost their deterrent value.

The €80 cost of releasing a clamp has not increased since its introduction in 1998. Mr Keilthy, who deals with appeals against Dublin Street Parking Services, said the “real deterrent effect” had diminished with a substantial number of repeat offenders.

His analysis of the frequency with which cars were clamped in the last four years showed that almost 30 per cent had been clamped more than once. Almost 400 cars were clamped more than 10 times, four cars were clamped an average of once a month, while the “most persistent offender” was clamped 63 times.

In his annual report to Dublin City Council Mr Keilthy said clamp-release charges should be increased by more than 60 per cent to €130 to cover the actual cost of the service, and to preserve the deterrent effect.

The service cost the council about €7 million a year, which could be fully recovered only if the charge was increased to €130, he said. Otherwise it would continue to be subsidised from the meter fees paid by compliant parkers.