The value of unpaid court fines quadrupled from €5.8m in 2015 to more than €20m last year, after the law was changed to reduce the number of people going to jail for non-payment.

The rise in non-payment is causing administrative difficulties in many district courts, where thousands of extra bench warrants must be generated to force defaulters to return.

More than 154,000 people have been fined under the Fines Act 2014 since it came into effect in January 2016 and 85,000 of them failed to pay the penalty levied. A large number of the fines relate to speeding offences.

The rate of non-payment is more than four times greater than before the Fines Act became law. About 158,000 people were fined by the courts between