Accused mosque killer's manifesto likely to be limited in any trial

The accused mosque shooter is unlikely to be able to use his court trial as a platform for his political views, criminal and media law scholars say.

Auckland University criminal law professor Khylee Quince said Brenton Tarrant could potentially face 50 counts of murder to reflect the magnitude of the massacre, rather than charges under the Terrorism Act.

Brenton Tarrant, 28, so far faces one charge of murder over Friday's massacre, but police have said further charges will be laid.

Over the weekend, he told his duty solicitor he did not want further legal representation.

That, combined with the online publication of ideological material immediately before the shootings, has raised fears he could use the legal process as a means to grand-stand, amplified by global media coverage of the case.

However, Otago University legal issues centre director Bridgette Toy-Cronin said the court had tools to limit the risk of Tarrant using the trial to disseminate his views.

"I'd expect them to deploy all of them, or as many of them as they can," she said.

The court was likely to appoint either an amicus lawyer to advise the court on points of law, or a stand-by lawyer who could step in at any time if the judge deemed it appropriate.

"They're on stand-by if the defendant becomes incapacitated, maybe because (he is) being disruptive... The court might decide that they are the person they want to hear from on certain issues rather than the defendant - and that can be done without the defendant's consent."

That was particularly likely during any cross-examination of witnesses, Dr Toy-Cronin said.

If the defendant became disruptive or did anything else that "affronts the administration of justice", he could be found in contempt and removed from court.

"They're not going to roll that out at the drop of a hat, but it's there if it's needed."

Murder charges more likely

To limit the potential for political material being entered as evidence, Dr Toy-Cronin said the Crown was more likely to charge Tarrant under the Crimes Act, rather than the Terrorism Suppression Act, as some had called for.

"If it's murder charges, then what the Crown has to prove is that people died, that he intended to kill him, and so there's just less scope for all the other ideological stuff.

"The terrorism offences go further and talk about proving that it was ideologically motivated, so once you're into that territory you've got to bring in more evidence about whether it was ideologically motivated and that sort of opens the door to that bigger discussion.

"The fewer issues that are on the table the less things you've got to talk about basically."

That could signal to some people that the shootings were not being regarded as terrorism, even though Prime Minister Jacinda Ardern had said it was, she said.

Ms Quince said there was an option available to limit that public pushback, by charging Tarrant with 50 separate murder charges, rather than the common practice of laying a handful of representative charges.

"I think it's incredibly important in this particular instance, for reasons of public policy and to pay respect to the dignity and mana of the victims and survivors, to bring 50 charges of murder and then however many more charges of attempted murder."

That would "fully reflect the gravity and magnitude of this offending", Ms Quince said.

It would also be an "immense undertaking" as there was no possibility of a judge-alone trial.

"That's going to take many, many months of trial - that's an incredible burden on 12 members of the New Zealand citizenry to sit as a jury for that trial."

Everyone involved in the trial would need significant support and care, and there was already a precedent from previous gruelling trials for jurors to be excused from any further jury duty for life, she said.

Heavy reporting restrictions likely

Canterbury University law dean Ursula Cheer said restricting how media could report the case could lower the risk of giving Tarrant more publicity.

"Prominent murders often have enormous interest in them... but because of the extreme sensitivity around this one, I think it's highly likely to see more suppression and restrictions on reporting [than usual]."

The recent trial and conviction of Cardinal George Pell in Australia was suppressed from all publication until after his sentencing, and that could be an option to prevent weeks of rolling coverage in this case, Dr Cheer said.

"The public gets [open justice] in the end. So if it's necessary for there to be suppression for some time, until sentencing, say, then that may be a good idea and it should be considered."

If ongoing coverage was allowed, there were other options for suppression, she said.

"If the accused did do a great big rant and rave that was just unacceptable, the judge could stop and make an order that none of that information was to come out or be reported."

Although suppression orders did not apply to overseas reporting, they would still help to limit publication, she said.

Media both here and overseas also have a responsibility to exercise self-restraint.