"In setting up the scheme that way, the government of the day removed the right for people to sue for damages following an injury, which means we cover all injuries irrespective of the situation - with the exception of wilfully self-inflicted harm, which we do not always cover," he said.
However, not all agree that boxing should be covered by ACC and question its accidental nature.
Bruce Rogan, from Mangawhai, wrote to the Herald to express his disapproval.
"It has been widely reported in the media that a blow to the head of someone in a boxing ring is an accident.
"Many of us were under the impression that hitting the opponent's head was the main purpose of the fixture," he wrote.
"If it was an accident, ACC will pick up the tab and if there is permanent brain damage that tab could by millions of dollars.
"ACC levy payers will be paying for the easily foreseeable consequences of this piece of latter-day gladiatorial combat.
"The fact an untrained, unskilled person can get into a boxing ring at all is bad enough. The fact that such a person can get fixed by generosity of the community is much worse."
Sports injury research specialist Dr Doug King said things become very confusing when you started to unpack who should and shouldn't be covered by ACC.
"You have to draw the line somewhere. It depends on what side of the glass you are looking at it, whether it is half full or half empty, as to whether it is or isn't wilfully self-inflicted or not.
"Driving a car at 120km/h and crashing, is that wilfully self-inflicted harm? Someone jogging down the road, for a person who hates jogging, is that wilfully self-inflicted harm?" he said.
Legendary boxing referee Lance Revill said he was riled by the suggestion boxing shouldn't be covered by ACC when there were plenty of other sports with high injury rates, such as rugby and rugby league.
"There have been deaths in rugby but they all stay quiet because it is our number one sport, but as soon as it is something like boxing everyone jumps on the bandwagon to ban the sport," he said.
"The problem is people opening up boxing gyms that know nothing about the sport and clearly just want to make a buck out of tournaments.
"We have to sort that out but boxing has been around a long time so it is crazy to talk about banning the sport."
Boxing New Zealand president Keith Walker said most serious injuries in the sport come from the professional boxing scene, however amateur boxing had a very good safety record.
"The concussions statistics would not be related to the amateur side of the sport at all.
"For instance when we have an international competition, where there is somewhere around 350-odd bouts, we have nil concussions.
"But we do have a lot of cuts, I do admit that, and more so now because they have taken the head guards off the elite male boxers, therefore most of the injuries we have are cut eyes and brows."
However, Walker said the essence of boxing was not causing injury but about skill.
"It is certainly a contact sport but there are so many safety aspects around that. You just can't look at it from a point of view of 'he is going to try and punch that guy so it will cause injury'.
"That is certainly not the case, in actual fact there is more skill factor to it than the desire to cause serious injury to the opponent. That is not the essence of the sport at all."
Kain was fighting former Canterbury and Tasman Makos rugby halfback Steve Alfeld when he was critically injured. He died four days later in Christchurch Hospital.
Earlier this year Lucy Aroha Brown died in hospital after suffering a head injury during a routine sparring session.
The mother of two was flown to Auckland City Hospital in a critical condition, after she collapsed during routine sparring at Wellsford Boxing Sport & Fitness Club in August.
In 2016, Neville Knight also died during a charity fight in Hamilton. The 49-year-old collapsed in front of hundreds of spectators at the event on September 24.
