Pike River families say former mine boss Peter Whittall is being treated differently by the justice system, simply because he has more money.
The families, led by Anna Osborne, Sonya Rockhouse and Bernie Monk, are in the Supreme Court today for a last ditch bid to have Whittall prosecuted over health and safety breaches.
WorkSafe had originally brought 12 charges against Whittall, but they were dismissed after Whittall agreed to pay $3.41 million to the families.
Nigel Hampton QC has today told the Supreme Court justices that the justice system had to be the same for all, whether rich or poor.
"Or is it a system where a payment of a sum of money can be used to curtail and put to an end a prosecution?
"We say that this is what occurred here."
Hampton said Whittall still claimed he was innocent on the health and safety charges, and didn't accept responsibility for the mining disaster.
He argued there was enough evidence to continue with the prosecution, and the only reason it was dropped was because of the payout for the families.
"The offer of money, or this 'voluntary payment', shouldn't have entered into this at all," Hampton said.
"Either the prosecution had a case, and it should have gone to trial. Or they didn't have a case, and it shouldn't have gone to trial.
"Either way, the money is irrelevant."
He said it set a "dangerous precedent" if the charges were allowed to be dropped.
"Directors cannot just hide behind the corporate veil. They do have responsibility.
"This [lack of] prosecution gives a message to directors that they cannot simply hide from prosecution."
But WorkSafe lawyer Aaron Martin told the court that, although a payout was agreed, it wasn't the final word on whether or not they went ahead with a prosecution.
"What you have in this case is an independent prosecutor, that is looking at a range of factors, and not going to receive the money or have financial gain from the decision.
"In my mind, what you have here is a difficult prosecutorial decision.
"There was an understanding that if charges were not pursued then this money would be paid, but that does not mean a deal was made.
"What's being superimposed on these discussions is this idea that nothing else was in play.
"[But] we're talking about a 16 to 20 week trial, with a number of witnesses that would not have been available."
Before today's court case, Anna Osborne said the families wanted a moral victory, and for someone to be held account.
"We thought that was an unjust decision and we thought that was blood money and you can't buy your way out of justice in New Zealand, or so we thought."
The Supreme Court Justices have reserved their decision.