Shann later told Hawke's Bay Today he had been fighting ACC for the release of medical documents relating to a back injury he sustained in 1996.
He said ACC had "withheld" up to 27 medical reports from him and the judicial system over the past 16 years which had resulted in a decision in 2003 from a District Court Judge that he was no longer eligible for ACC payments.
Shann said ACC released only six of his many medical reports for the judge to assess when making his decision.
He said the rest of the medical reports were buried in the system.
Since then, Shann said an ACC worker had been providing him with the medical reports anonymously which told a tale of his inability to recover from injury and need for treatment.
He also claimed his original injury was made worse by physiotherapy he received following the incident and a fall he took during a back pain study for ACC. A total of six injuries within four months.
He said ACC told him all of the injuries should have healed within six weeks, even though many medical reports he has since obtained tell a different story.
He said the original court decision, based on the six medical reports which did not give an accurate picture of his physical state, meant an ongoing battle for him.
"It's not just about me anymore, about my back. I'm destined to be crippled and in pain 24 hours a day.
"This is an issue of justice. It's not just me getting screwed over, they're doing this to thousands of people."
He said he has been unable to fully partake in work for the past 16 years and has not been able to sleep more than two hours at a time due to pain.
He has migraines 80-90 per cent of the time.
When contacted by Hawke's Bay Today a representative for ACC said, "ACC are not withholding any medical information".
He pleaded guilty to sending the email and was ordered to reappear before the courts for sentencing should he reoffend within the next six months.