Some prisons are banning a newsletter that offers inmates advice on human rights and peaceful protest out of fear the pamphlets pose a threat to the security of the prison.
Produced by People Against Prisons Aotearoa, Corrections Doesn't Want You To Read This, is the sixth issue of the prison newsletter.
The previous issue was referred to police by Corrections over concerns it encouraged prisoners to riot.
The latest edition accuses Corrections of curtailing freedom of speech and expression by confiscating issue 5 of the newsletter from prisoners.
It encourages prisoners to create committees to "find non-violent solutions" to ensure their human rights are upheld.
People Against Prison Aotearoa spokesperson Emilie Rākete said the group has received at least 20 complaints from prisoners across the country that Corrections is withholding the newsletter from them.
She said it was a breach of prisoners right to freedom of expression.
"They're trying to stop incarcerated people from discussing what they do to incarcerated people.
"And we've seen this year what it looks like when people in prisons don't feel like they have any meaningful way of addressing their problems.
"It looks like the Waikeria uprising, it looks like Mihi Bassett harming herself in her prison cell, and those problems won't go away if the Department of Corrections bans a newsletter," Rākete said.
The newsletter includes an article by a prisoner on how to use the prison complaints system.
By banning the newsletter, Rākete said Corrections was actually at risk of creating unnecessary tension.
"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.
A letter from Corrections in response to a complaint from a prisoner in Invercargill quotes the chief custodial officer as saying the publication promotes non-violent protests.
"The thrust of the information being provided is to encourage the pursuit of freedom of speech through non-violent protest, however, any protest in a prison is likely to endanger the good order of the prison," the letter said.
It said protests would "endanger the good order of the prison" and prisoners would likely be charged under the Corrections Act 2004, and given a lawful order to desist.
Human rights lawyer Douglas Ewen said there was not legal grounds for this, as Corrections could only withhold mail if it threatened the security of the prison.
"Now security and good order of the prison under the Corrections Act are two different things and the department, in its own interests, is conflating the two.
"They're also saying that if you do this we will charge you with a disciplinary offence, they are effectively threatening them," Ewen said.
He did not accept the newsletter was inciting any protest, but merely advocating for prisoners to organise and liaise with people outside of the wire.
"Corrections wants to stifle that from happening because it doesn't want people to know what's happening in prisons."
Corrections would not give an interview but in a statement, said they were aware of four complaints from prisoners about the newsletter being withheld.
They say the view expressed in the Invercargill complaint was actually that of a national office staff member and not the chief custodial officer, Neil Beales.
In his statement, Beales said prison directors at a number of sites made the decision to withhold the newsletter "because they considered that they may pose a threat to the security of the prison, and promote or encourage the commission of an offence.
"Prison directors considered that the content of the newsletters could be interpreted by prisoners as an encouragement to take action in a way similar to the prisoners who started the Waikeria Prison riot," he said.
Corrections said there was no blanket prohibition of People Against Prisons Aotearoa newsletters and decisions to withhold mail were made on a case-by-case basis.