The country's biggest recreational fishing group is calling for a royal commission into the Ministry for Primary Industries' handling of an investigation into commercial fish dumping.
No-one was prosecuted even though there was evidence the practice was widespread.
And another report reveals skippers had even admitted guilt.
There are other examples of MPI not taking action over illegal dumping.
Another report in 2009 involved the monitoring of 42 vessels. Half were allegedly dumping fish illegally and again, no action was taken.
Despite these reports, MPI remains adamant that it still has a "robust" management system.
Martyn Dunne, the Director General of MPI, says he's "not interested in affording blame to individuals" and "the focus must now be moving on".
Video of not only fish being dumped on multiple vessels, but dolphins being hauled in too, started it all.
That illegal activity was documented in a 2013 preliminary report, released publicly by Newshub.
The recently-released final version of that report reveals that skippers not only admitted guilt, they told investigators they don't even bother recording their catch properly in log books.
One tells MPI's investigator: "I've been a criminal all my life you just haven't caught me. If I was to record every species that I ever caught in my whole fishing career mate I would need a bloody, a list of books a mile high".
Forest and Bird campaign manager Kevin Hackwell says it's "an incredibly bad look".
"It goes to the fundamentals about how the Ministry manages our fisheries," he says.
The skipper goes on: "I put my hand up and said I have never been not guilty... I'm sick of being a bloody criminal".
Another skipper admits he doesn't even understand the rules, telling MPI when quizzed about dumping elephant fish, "I'm not 100 percent".
Despite such admissions, the video, and a recommendation to prosecute, nothing happened.
MPI has repeatedly publicly denied the fishermen had immunity from prosecution despite an internal email from the Director of Fisheries saying he believed there was "implied immunity".
LegaSea's Richard Baker says they've misled the public and the recreational sector says that's not good enough.
"MPI are involved up to their necks in what has been going on - the systemic dumping - and there's only one way that's going to be resolved and that is a royal commission of inquiry," Mr Baker says.
Minister for Primary Industries Nathan Guy accepts the decision making by his officials was "flawed" - but he still has confidence in them.
"They didn't go for a prosecution and I'm very disappointed they didn't follow through with that."
Green Party fisheries spokesperson Eugenie Sage says Mr Guy needs to take a look at what's happened.
"The Minister should be seriously reflecting on his failure to stop illegal dumping and the mismanagement of fisheries which is occurring on his watch."
MPI is now an agency under serious scrutiny.
Newshub.
