Bay of Plenty road policing manager Inspector Kevin Taylor said the crash warranted a lengthy investigation.
"This was a very serious crash - one of the worst and most upsetting, in terms of the number of young victims, that had ever been attended by many of our police staff and other emergency services.
"In order to do justice to the victims and their whanau, their schools, the local community and transport users around New Zealand, it was absolutely critical that the investigation was thorough and robust," he said.
Only 16 of those hurt in the crash had injuries serious enough to to warrant charging the driver under the Land Transport Act.
Mr Taylor said the investigation and crash analysis concluded the truck driver caused the crash when he failed to manoeuvre around the school bus.
The incident continued to be a clear reminder for all road users about the rules when passing school buses, he said.
The speed limit when passing a stationary school bus is 20km p/hr. Drivers should aware of young children when around school buses and need to take extra care when driving passed school buses, police said.
Meanwhile the bus driver still has not returned to work after the crash left him "traumatised".
Transbay Coaches operations manager, Stu McNabb, said the local man was still very shaken and did not have any plans to get back behind the wheel of a bus.
"I went out to visit him and he's made it pretty clear that he wouldn't be happy about coming back - it was all pretty traumatic for him."
The man's granddaughter was the 8-year-old girl who was left fighting for her life after the crash.
Mr McNabb said the young girl had made a full recovery and was now "fine".
He said he always knew the bus driver wasn't at fault and hoped he would one day return to work for them.
"He was pulling in to drop some kids of then 'boom'. All we want to know is what happened to the logging truck driver - did he have a heart attack or did he fall asleep at the wheel or was he over his driving hours?"
Mr McNabb said he would be at the Whakatane District Court when the truck driver appears on February 23.
- additional reporting APNZ