Airlines will not stop breaching New Zealand's border rules unless they are likely to face prosecution, Labour Party says.
Jetstar has been fined $12,000 for allowing a deported passenger to fly back to New Zealand despite being told three times not to let him on board the flight.
Immigration New Zealand said Jetstar's check-in agent at Bangkok airport eventually overrode the do-not-board directive by changing the Chilean passenger's name.
It said Jetstar had a poor compliance record, including 14 similar breaches, 300 infringements over four years and a previous prosecution.
Labour's immigration spokesman Iain Lees-Galloway said companies would not mend their ways unless they faced a realistic prospect of being prosecuted by the Ministry of Business Innovation and Enterprise (MBIE), and a substantial fine.
He said that could be down to a lack of resources for mounting a prosecution.
"Across the areas that MBIE is responsible for, and particularly about the Labour Department and Health and Safety, they have expressed a reluctance to prosecute, and I think that is tied to the fact that they simply don't have the resources."
Mr Lees-Galloway said bad publicity from the court case may do more than fines to change Jetstar's behaviour.
Maximum fine $50,000
Immigration New Zealand says it has previously prosecuted Jetstar.
The airline was convicted and fined $6500 in January 2012 for ignoring a directive not to board a Chinese national on a flight to New Zealand in January 2011.
The maximum fine for an airline failing to comply with obligations under the Immigration Act is $50,000.
The Act also provides for an infringement regime which Immigration New Zealand says was introduced in July 2012 as an alternative to prosecution, which can be costly and time-consuming.
It said 928 infringement notices were served in the 2014-15 financial year.
Chilean airline LATAM recieved 229 infringement notices in the past year - the most of any airline.
Most infringements related to passenger information requirements not being met by an airline.
Jetstar was the fifth worst offender receiving 64 infringement notices last year.
Qantas received the second highest number at 163, followed by Virgin Australia with 134 and Cathay Pacific with 70 infringements.
Air New Zealand received 25 infringements.