It is a condition that can cause memory loss, poor judgment and impulse, aggression and depression, suicidal ideation and eventually dementia.

In the case of Billy Guytonthe diagnosis followed his suspected suicide in May 2023, aged 33, and the donation of his brain to the Neurological Foundation Human Brain Bank at the University of Auckland.

After his son’s death, John Guyton wrote to Workplace Relations and Safety Minister Brooke van Velden calling for WorkSafe to intervene at the rugby pitch on the grounds that it was a workplace where players were injured.

Billy Guyton played for the Blues, Crusaders, Hurricanes and Maori All Blacks before retiring early from rugby aged 28.

The call for help was linked to John Guyton’s opinion that Rugby NZ was not doing enough to protect players, despite strong – though still inconclusive – links between CTE and head knocks through contact sport.

In August, WorkSafe investigations manager Rob Pope told John Guyton that WorkSafe recognized professional athletes as “workers” who were covered by health and safety at work legislation.

But he said the law said “businesses should know their work and their workplace better than anyone else”, meaning NZ Rugby was “best placed to understand and manage the specific risks to its athletes professionals, as he is primarily responsible for the care of his people’.

He said WorkSafe had the ability to carry out health and safety inquiries but “it would be difficult for us to progress beyond that due to the complexity of the issue and time constraints”.

“Complex matters such as brain injuries and their long-term impact may involve extensive consultation with experts and specialists before we can determine whether WorkSafe can intervene.”

He said concussion issues are getting more attention and growing public awareness.

“However, the reality is that WorkSafe does not have the resources or expertise to engage in an area that is not well understood and where there is no firm medical agreement about its causes.”

Pope told him Herald: “WorkSafe does not have the expertise to intervene in such a complex issue requiring long-term medical advice and is therefore not the most appropriate agency to do so.”

The Herald sought WorkSafe’s position beyond the Billy Guyton case and was told it had not engaged with NZ Rugby on the matter. It said its “recent strategic reset” means it is focusing on the areas with the biggest job losses, which are agriculture, construction, forestry and manufacturing.

A WorkSafe spokesman said the law puts responsibility on the employer operating the workplace and it is up to the employer to decide what to do.

“If a person’s work directly led to harm, this could indicate that an organization failed to fulfill its duty of care – even if the harm did not become apparent until some time later.”

John Guyton said he worked as a builder with health and safety issues understood for every job he undertook before work began.

“When you go to a construction site, the risks and dangers are pointed out to you.”

He said it was unclear whether professional rugby players had the same level of understanding when they took the field. He said it is not known if the risk was spelled out in the players’ contracts or if they were presented with research linking CTE to head hits.

He said he believed it was the core business for WorkSafe and was disturbed to see the complexity raised as a reason why the agency was not involved.

“Is it too complex not to worry about? Or do I just fight the fights I can win? He was stunned by their response – it’s their duty.

“That’s what they’re there for, to deal with the hard stuff, because we as an audience can’t handle it.”

NZ Rugby has developed an increasingly strict set of rules around concussion management, including extended periods of rest before playing again. It is also working with the New Zealand Rugby Foundation and the New Zealand Rugby Players’ Association on a “comprehensive and co-ordinated plan” on concussion and “head acceleration events”.

A major legal case against the National Football League in the United States has seen more than $1.5 billion paid out to more than 1,600 former NFL players. In the UK, around 850 former rugby players I’m suing the sports bodies that run the game there.

David Fisher is based in Northland and has worked as a journalist for more than 30 years, winning several journalism awards, including twice being named Reporter of the Year and being selected as one of a small number of Wolfson Press Fellows at Wolfson College, Cambridge. He first joined the Herald in 2004.

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