Official figures show just over a quarter of inmates released from the Maori Focus Units in the 2010 -2011 year reoffended within 12 months.
The data has been released to Te Manu Korihi under the Official Information Act.
The Department of Corrections says of the 400 prisoners who served their time in five Maori units, 108 went back to prison in the 2010-2011 year.
But it says the re-offending rate is 3% lower than for inmates in other parts of the prisons.
The Department's 2011-2012 report says Maori make up 50% of the prison population, and 30.4% of those were sent back to jail.
Corrections says no rehabilitation programme in the world has been able to prevent re-offending entirely.
But it says further expansion of initiatives such as the Maori Therapeutic Programme will help improve outcomes for inmates participating in Maori Focus units.
Meanwhile, outside of prison, the police aim through a strategy called Turning of the Tide to cut the prosecution of Maori people by 25% within six years with help from a number of iwi representatives.
Police aim to change the way they deal with people, to utilise Whanau Ora services, and get help from iwi that could work with troubled Maori such as enrolling them in trades training.