Mr Tomoana said Ngati Kahungunu was a co-claimant both with this current claim, as well as the original claim 10 years ago.
"At that time there was a disproportionate amount of Maori going through the Corrections system, they were getting longer sentences and less chance of parole, and programmes designed for them were ineffective," Mr Tomoana said.
"Ten years later things had got worse - it's frustrating we had to go back to the tribunal again to tell them things were no better.
"It's frustrating we have 10,000 tamariki with parents or grandparents in jail."
He said that although the Department of Corrections had made visible attempts to rectify the situation, it had gone backwards.
"We need to sit down with the Crown and devise ways to improve it.
"We have found that just because you have Maori programmes in Government departments it does not mean they will be effective.
"Although there are great programmes and officers, they are conducted in a foreign setting which overrides any cultural nuances that may have been offered in the programme."
He said this was one of the issues that would be explored when meetings were held with both local and national Department of Corrections heads in the next one or two months.
"We will be looking forward to these conversations with enthusiasm and optimism."
Key to any success, however, would be the willingness of the Corrections authorities to trust that tikanga programmes could work, and the recognition that the way things were set up had to change, he said.
"As iwi we can help but there has to be a positive demolition of some of the current structures to allow tikanga to operate - at the moment programmes within Corrections are straitjacketed by the system and will never work, even with the best intentions."
He added that the resistance to recognising Maori systems and customs needed to be broken down, and the "lock and throw the key away" mentality needed to change.