"It's hard to say if the initiative is good. I think it will be a very big incentive for people who need to get to work or need transport but, obviously, there are people who don't regard a licence as an essential thing."
Mr McLachlan said there were many different reasons why people did not or could not pay fines. He said Whanganui had relatively high levels of personal debt, particularly for small household repairs.
He said fines were a different form of debt to payments for goods or services but the money owed was just as real, and should be regarded just as important.
"If you don't break the law, you don't get a fine," he said. "No one likes paying fines, but it's an unfortunate reality that if you want to keep your licence you're going to have to pay them."
Nationwide, $11.6 million in fines had been paid as a direct result of the warning letters. Justice Minister Amy Adams announced the campaign had raked in $43.5 million in previously unpaid fines since February 2014.
Mrs Adams announced 30,000 warning letters had been sent in the two years to January 30.
However, documents released to the Chronicle showed 19,567 letters were sent since the initiative started in February 2014.
The Ministry ceased actioning stop orders on July 1 last year, and was "changing procedures ... to make them more effective" - but continued to send warning letters.