While the man who was arrested claimed officers had sworn at him and he would have complied if he'd known he was under arrest, police said the man resisted and failed to comply to repeated attempts to subdue him.
While only one officer had gone to arrest him, two others had felt compelled to help resist him as he continued to fight.
The man's injuries happened when he was put into a cell in the police van and his hand got trapped in the door. The incident was reported to the IPCA.
When police became aware of his injuries they took him straight to hospital.
In early May a female sergeant went to where he was living to issue the court summons.
The man had been joking with her about dropping the charges because of his injuries and she responded in a like manner, joking "it is not very fair is it ... we can't finger print you in the future".
The man found the joke offensive.
The man claimed this remark was offensive and later laid a complaint over his arrest and what he saw as an inappropriate joke about his finger.
However, the authority has deemed his arrest was reasonable, police actions were on the whole justified and his injuries were accidental.
It did, however, caution one officer that the use of mastoid thumb pressure was no longer an approved tactic, and deemed the female officer's joke was not professional.
Police have also reviewed the van design and made slight amendments to minimise the risk of future accidents.
Waikato District commander Superintendent Bruce Bird accepted the authority's findings.
He accepted one officer had used a tactic that was not approved and that another did not act in line with police values when communicating with the man several weeks later.
"These are difficult and challenging incidents to deal with," he said. "The subsequent debrief has made our staff aware of other courses of action that can be considered in such circumstances."
Because of employment reasons police are unable to outline any specifics of action taken.