Corrections Minister Kelvin Davis admits his department is withholding a newsletter about peaceful protest and human rights from some prisoners.
Four inmates have complained to Corrections that a newsletter by People Against Prisons Aotearoa, offering advice on human rights and peaceful protest for prisoners, is being withheld from them.
Corrections said it had refused to deliver the newsletter on the grounds it encouraged non-violent action and protests that could endanger the good order of the prison.
Corrections chief custodial officer Neil Beales said prison directors at several sites withheld the newsletters "because they considered that they may pose a threat to the security of the prison, and promote or encourage the commission of an offence".
Human rights lawyer Douglas Ewen said prisons did not have legal grounds to stop the newsletter reaching prisoners, unless it genuinely threatened the security of the prison.
He did not accept the newsletter could incite protest and said it advocated for prisoners to organise and to liaise with people on the outside.
"Corrections wants to stifle that from happening because it doesn't want people to know what's happening in prisons," Ewen said.
Davis said prisons made the decision on a case-by-case basis, and he did not direct them to withhold the newsletter.
"I haven't read it and I'm not interested in reading their newsletters," Davis said.
The newsletter that was withheld is called Corrections Doesn't Want You To Read This, and is the sixth issue of the publication.
Corrections referred issue five to police, because of concerns it encouraged prisoners to riot.
The latest edition accused Corrections of stopping freedom of speech by confiscating issue five and includes an article by a prisoner on how to use the prison complaints system.
People Against Prison Aotearoa spokesperson Emilie Rākete said the group had received at least 20 complaints from prisoners across the country that Corrections was withholding the newsletter from them.
"All that it does is force that criticism underground, it forces it to be silent and it pressurises it.
"When people are angry, and they're being abused and nobody is listening, you get problems.
"We can provide a meaningful outlet to the very valid and completely legitimate frustration that people in prison feel through our newsletter, through our non-violent organising strategy for prisoners," Rākete said.
Davis said prisoners already had information about how complaints were dealt with.
Corrections was improving its systems by moving away from a paper-based system and "removing the middle man that is often the Corrections officer", he said.
A kiosk style system was going to be rolled out, Davis said.