In a summary judgment in March, Judge Tony Zohrab said the company was responsible for the fire as it could have done more to deal with the risk of the tree.
But lawyer for the company Jane Forrest told the High Court at Wellington today that Marlborough Lines had not been negligent and did not breach its statutory duty when the fire happened.
"Judge Zohrab's suggestion that Marlborough Lines could take a more proactive role ... actually is without any legal basis," she said during today's appeal against the summary judgment.
Regulations were in place in which the company could compel landowners to cut or trim trees within 7.5m of the lines.
The tree in question, which was 20m tall, was more than 10m away and so was outside the zone Marlborough Lines had control over.
They had no authority to make the landowner chop down the tree, but Judge Zohrab found they should have communicated with the landowner over the risk the tree faced.
"In my submission, the evidence does show Marlborough Lines has taken all reasonable steps to prevent this," Forrest said.
The company works closely with the Fire Authority and would modify circuit breakers over high risk periods. At the time of the incident there were three patrollers inspecting the lines.
Each area in the network is inspected once every two or three years, and Marlborough Lines communicates with landowners by way of newsletter and its website, reminding them to be vigilant with trees close to the lines.
In a similar case, a different judge noted the particular section of the act being relied upon was badly crafted.
"There can be no doubt that the hand that drafted S.43 faltered badly. It is extremely difficult to say with any confidence just what the section was intended to mean," the judge said in that decision.
Today's arguments have focused on legal interpretation of the Act.
Lawyer for the Fire Service Commission Bruce Scott said the company should have spoken to the landowner about the tree, and if the owner had then refused to deal with the tree they might have had a defence.
The tree was young and healthy.
He said lines companies had options of moving lines, putting them underground, adjusting circuit breakers, and using fault protection mechanisms to cut power to the line and prevent relivening where there is an increased risk of fire.
"The lines company knows full well that its lines have the potential to cause fires and do cause fires all over New Zealand."
Judge Peter Churchman has reserved his decision.