Cable ties and restraint chairs are set to be approved for use on children in custody as young as 10 if new laws pass the NT Parliament next month.

Key points: The bill will clarify use of restraints in NT

The bill will clarify use of restraints in NT Attorney-General said that could include cable ties, restraint chairs

Attorney-General said that could include cable ties, restraint chairs Advocates say restraints should not be used on juveniles

The restraint chairs are similar to those used in Guantanamo Bay and Australia's adult prisons.

The Youth Justice Amendment Bill 2016, introduced to Parliament on Thursday, clarifies what restraints can be used on juveniles in detention and what circumstances justify the use of "mechanical devices."

"All of these devices would only be used for the safety of the detainee themselves, the safety of the staff and for the good order and operation of a detention centre," NT Attorney-General John Elferink said.

"Traditionally the reference has been to handcuffs but there are also waist belts, other systems by which you restrain hands to waists and you can also place legs into some form of restraint strap.

"There are any number of these devices which can be applied."

Under the changes, the Commissioner for Corrections would decide what types of restraint were officially approved but the Attorney-General said cable ties and restraint chairs could be included.

"If necessary that's something that would be considered," he said.

The NT faced a barrage of criticism after the ABC reported the case of Dylan Voller, 17, who was taken from juvenile detention to the adult prison in Alice Springs and restrained in a "safety chair" for close to two hours with a spit hood over his head.

Chief Minister Adam Giles pledged to investigate the incident, which was videoed by Corrective Services. The report is expected to be released in May.

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Restraint chairs already used in the NT

Restraint chairs, which are used to strap a person around the chest, waist, shins, ankles and shoulders to a padded chair, are already used on juveniles in the Northern Territory.

What is a spit mask? A hood typically made of fabric that blocks a prisoner from spitting at a guard

A hood typically made of fabric that blocks a prisoner from spitting at a guard Designed to prevent transmission of infectious diseases

Designed to prevent transmission of infectious diseases Used on juveniles in WA, SA and the NT

Used on juveniles in WA, SA and the NT Not used on juveniles in NSW or Tasmania

In March 2015, Dylan Voller was taken from a juvenile detention to the adult prison in Alice Springs and restrained in a "safety chair" for close to two hours with a spit hood over his head.

A Department of Corrections incident report said Mr Voller was restrained because he had threatened to self-harm while in his cell.

Mr Voller described the incident to his mother over the phone.

"He had a bag or a mask or something maybe tied over his head or put on his head and was like restrained in a chair or something for quite a bit of time," Joanne Voller told the ABC.

"To be honest, quite a few of the things that I've heard have happened — I hear it but I have to let it go because if I stored up every time he rang me and the things that have happened in there — I think I'd be even more of a mess than what I am right now."

Mechanical restraints 'shouldn't be used at all'

Priscilla Collins, chief executive of the North Australia Aboriginal Justice Agency (NAAJA), said restraints should not be used on juveniles at all.

Restraints in other jurisdictions: Victoria: Handcuffs are the only mechanical restraints used in Victorian youth justice centres.

Victoria: Handcuffs are the only mechanical restraints used in Victorian youth justice centres. Queensland: Handcuffs, zip ties (also known as cable ties), helmets, restraint sleeves, ankle cuffs and escort cables can be used if "there is no other way to stop the child attempting to escape; or seriously harming himself/herself or someone else; or seriously disrupting order and security at the detention centre."

Queensland: Handcuffs, zip ties (also known as cable ties), helmets, restraint sleeves, ankle cuffs and escort cables can be used if "there is no other way to stop the child attempting to escape; or seriously harming himself/herself or someone else; or seriously disrupting order and security at the detention centre." NSW: Does not publish its list of approved restraints, which may be used if "the young person is behaving in a way that "he or she might seriously injure himself / herself or another person" unless they are restrained.

NSW: Does not publish its list of approved restraints, which may be used if "the young person is behaving in a way that "he or she might seriously injure himself / herself or another person" unless they are restrained. WA, SA: Types of restraints used are confidential and may only be used to prevent injury, escape or on medical advice.

She said NAAJA, which represents young Aboriginal people in detention, was concerned by the amendments.

"The biggest concern is how you interpret that legislation and how far that's taken," she said. "Because really it shouldn't be used at all."

"All it does is bring more trauma to that child and we're not actually working with them on therapeutic models to deal with the trauma and deal with why they're coming into contact with the criminal justice system."

The president of the Criminal Lawyers Association of the Northern Territory, Russell Goldflam, said he supported the Attorney-General's changes.

"I think the amendments are going to be mildly helpful because what they will do is regulate and structure the use of these restraint mechanisms by youth detention officers," Mr Goldflam said.

"At the moment the law isn't really clear."

He said the changes would also help in future cases similar to Mr Voller's.

"I think that these amendments mean that that sort of quite-disturbing incident is unlikely to be repeated," he said.

"Previously, the authorities who used those rather-extreme measures against that young person didn't really have statutory guidance as to where the limits of the use of that power and those measures lay."