"But it doesn't end there because in what can only be described as a frenzied attack, you, Greene continued to punch the victim in the head and pulled his keys from the ignition and tossed them away."
Isabeth was sentenced to five months' home detention and Greene to four months' community detention and 100 hours' community work.
On December 13, the pair were travelling behind a rental van being driven by an Australian national, Chehan Lasika Senasekera, from Hokitika to Greymouth. Angered by the manner in which the van was being driven they followed it into central Greymouth, and ultimately up a dead-end street.
Greene then ran to the van, wrenched open the door and started punching the driver about the head. When the tourist asked, "What have I done wrong?" Greene said: "You nearly f...g killed us."
As he continued the attack, Isabeth struck the victim once with the hammer, leaving puncture wounds on his right hand, left forearm and right inner thigh. Greene then delivered more punches, wrenched the keys from the ignition and threw them up the road before driving off.
The tourist told police the hammer used in the attack was covered in white powder and the hammer found in Greene's van was not only covered in white powder but had fresh blood on the head.
In his victim impact statement, Mr Senasekera said he had travelled through 20 countries and never experienced anything like the attack before.
Lawyer Richard Bodle said the attack was a "complete aberration" for both men, who were extremely embarrassed and their employer was beside himself at the potential loss of two good workers if they were jailed.
"They were swept up in the emotion, like a hound with the source of a scent," Mr Bodle said.
He said Isabeth retrieved a hammer from the work van and brandished it, but he could not recall taking it out of the vehicle and nor could Greene.
However, Judge Kellar said the victim's wounds and blood on the hammer were evidence that it had been used.
