She told the Herald that businesses are responsible for making sure they know the law – unless they want to pay the price,
"We encourage all businesses and individuals to make sure they understand the law relating to cartel conduct, so agreements to fix prices, allocating customers – this is all cartel conduct which can attract high financial penalties or even prison."
The scheme was only operating for a month between October and November 2020, but Rawlings said it only ceased when the Commerce Commission began investigating.
Jenna Raeburn, the general manager of corporate affairs of Wellington Airport, says she's glad the issue was solved quickly.
"It is concerning this has happened but the Commerce Commission has got on to it and addressed it so we're moving on ... we want to see fair behaviour from taxi companies and fair prices for consumers with good levels of competition."
The High Court imposed the penalties on Thursday, which will be payable in instalments over the next four years.
It initially found the appropriate starting point for fines would be within the range of $500,000 to $600,000 but took "mitigating circumstance" into account, as well as Hutt and City's financial position.