New Zealand authorities have admitted they messed up by allowing the accused Christchurch mass murderer to send a hand-written letter from his prison cell, after the document in question was shared online.

A six-page letter from Brenton Tarrant to a supporter was shared on 4chan this week. Though relatively innocuous – it mostly discusses a trip Tarrant took to Russia in 2015 – the letter has raised serious questions, especially in the light of the recent El Paso shooting, where the alleged killer cited Christchurch as an inspiration.

NZ Corrections Minister Kelvin Davis says that Tarrant’s letter should never have left the prison, but also says that inmates do have the right to send and receive mail.

We have never had to manage a prisoner like this before – and I have asked questions around whether our laws are now fit for purpose and asked for advice on what changes we may now need to make.

“I have made myself clear that this cannot happen again,” Davis went on to say.

Correspondence from Tarrant appearing on 4chan is particularly sensitive given recent discussion around the site’s offshoot 8chan, which was a locus for white supremacist activity before being taken offline last week. Before the Christchurch mass shooting, which left 51 people dead, Tarrant is alleged to have uploaded a 74-page manifesto outlining his fascist belief system.

Tarrant has pled not guilty to a series of charges including murder and attempted murder. His trial is set for next May.

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