Ms Graf could not be revived after skiing into an unpadded, wooden post of a fence guarding a reservoir at the bottom of Sugar’s Run on the morning of September 21.
A pathologist found the cause of the 60-year-old’s death was blunt force and cardiac trauma.
In his decision, Judge Geoff Rea accepted WorkSafe’s contention that NZSki exposed Ms Graf to a risk of death or serious injury by failing to adequately assess the risks associated with the fence.
The company, which also owns The Remarkables and Mt Hutt ski areas, was convicted on the charge, which carries a maximum penalty of $1.5 million.
A sentencing hearing is expected to take place next month.
During the judge-alone trial in the Queenstown District Court in April, WorkSafe alleged the company’s risk assessment of the fence was inadequate and "safety catch net fencing" should have been put in place along its full length at the bottom of the run.
Ms Graf, a highly experienced skier and longtime resort resident, had previously worked at Coronet Peak as an instructor.
Witnesses said she did not appear to be out of control and skied into the post without raising her hands or taking other evasive action.
Judge Rea said skiers usually made a right-hand turn at the base of the run, then skied parallel to the fence.
Although 10 of the posts were padded at the time of the accident, others further away from the usual turning point were not.
Because the fence had been built to keep skiers out of the reservoir, it was "obvious that skiers could ski into the fence as well".
Evidence presented by WorkSafe about a "padding hazard register" document, written by a ski patrol member in 2014, was "extremely significant", he said.
In the document, discovered on a computer by the company during WorkSafe’s investigation, the patroller recommended 28 fence posts be padded.
"It was aware that several serious harm injuries had occurred already, and that there had been many near misses."
However, he could not conclude from the evidence that the company should have had safety catch net fencing along the full length of the base of the run at the time of the accident.
NZSki chief executive Paul Anderson said it accepted the judge’s comments it was the company’s duty to "ensure it performed adequate risk assessments to identify all the hazards and risks" at the ski area.
However, before Ms Graf’s death, it had considered such an event to be of "low probability".
"Prior to Anita’s accident, we simply didn’t forsee that someone could ski into the fence at that location."
After the accident, it immediately installed a safety catch net fence, and made a full review of its terrain and structure hazard management system at all its ski areas.
"None of the changes we’ve made reduces the impact of Anita’s family’s loss, and we’re very sorry for them and continue to keep in contact."
A family member told the Otago Daily Times they did not want to comment on the decision.
— Guy Williams, PIJF court reporter
