Motorists in NSW and Victoria have saved more than $6 million by appealing parking and speeding fines over the past year, Freedom of Information documents reveal.
In NSW, 13,974 clued-up drivers successfully appealed fines, avoiding payments totalling $4.7 million between 2007 and 2008, according to figures obtained by consumer advocate Choice.
It showed almost a third of all drivers who argued their case were proven correct.
And the strike rate was even better in Victoria, where 45 per cent of motorists appealing against parking infringements were successful.
They saved at least $1.7 million by correctly blaming faulty parking meters, hard-to-read or missing signposts as well as other blatant errors made by ticket inspectors.
It was a clear sign drivers should not have to cop incorrect or unfair fines, Choice spokesman Christopher Zinn said.
"Choice in no way condones speeding or illegal parking but there are inevitably cases in which an automatic fine or conviction without reviewing the full circumstances may be patently unfair," he said.
"There are systems of appeal and, as with any other dispute resolution system, it pays for consumers to understand them and how they work."
Only 10 per cent of parking fines in Victoria or 166,817 were appealed in the financial year ending June 2008.
But as a result 59,539 fines were withdrawn, while a further 17,543 were replaced with a warning.
It proved persistence sometimes pays off, Mr Zinn said.
In 2007/2008, NSW motorists saved $3.21 million in parking fines after 23,816 out of 81,326 cases were successfully appealed.
Contesting speeding fines also produced savings, preventing 11,658 drivers from forking out $1.53 million, out of a possible 43,805 cases.
It was important all drivers were aware of their rights in fighting unfair fines, given the avenues of appeal differ from state to state, Mr Zinn said.
For example, you can appeal speed camera fines in NSW if you have a good driving record over the past decade, whereas Vicroads only look at the past two years.
On the flip side, Adelaide doesn't consider driving records at all.
Mr Zinn urged all motorists to take a closer look at their relevant appeal systems.