The Federal Government needs to "urgently" change sentencing laws for children convicted of terrorism offences because they breach international conventions, according to the independent watchdog for national security laws.

Key points: The Law Council president says terrorism laws are "not just about locking up kids"

The Law Council president says terrorism laws are "not just about locking up kids" He says the age of children charged with terror offences should be taken into account by a court determining bail

He says the age of children charged with terror offences should be taken into account by a court determining bail INSLM says the Crimes Act breaches the Convention on the Rights of the Child

Critics have argued that strict non-parole periods for jail sentences are in breach of Australia's obligations under the International Convention on the Rights of the Child, to which Australia is a signatory.

Limiting access to bail for minors charged with serious terrorism offences also causes a clash with the Convention.

More than 10 per cent of people convicted of terrorism offences in the last five years were under the age of 18.

The problems with parole and bail were highlighted by the Independent National Security Legislation Monitor (INSLM) James Renwick, in his report The Prosecution and Sentencing of Children for Commonwealth Terrorism Offences.

The review, handed to the Prime Minister last year but only tabled in Parliament last week, recommends a raft of changes.

Under the Crimes Act, anyone jailed for a serious terrorism offence is only allowed to apply for parole after serving three-quarters of his or her jail term.

Dr Renwick found that breached the Convention on the Rights of the Child because it prevented a judge from having the best interests of the child as a primary consideration.

"As these laws can be expected to be applied more in the coming years, this non-compliance ought to be addressed, and urgently," his report said.

Human Rights Commission welcomes recommendation

"The Convention on the Rights of the Child is clear that a court must always consider the best interests of the child as a primary consideration," said Human Rights Commissioner Edward Santow.

Mr Santow said being detained could be the defining experience of a child's life. ( Supplied: Australian Human Rights Commission )

"While we know that children can be susceptible to being influenced by bad people around them, they also have some of the best prospects for turning their lives around."

Arthur Moses, the president of the Law Council of Australia, told AM terrorism laws were "not just about locking up kids".

"Ultimately, we need to rehabilitate and re-integrate them back into our society, and I think that always has to be a fundamental focus when we are dealing with children," he said.

Bail can only be granted to people charged with serious terrorism offences where there are exceptional circumstances.

If the person charged is very young, their age should be a primary consideration, but that is not clear in the Crimes Act.

While not technically breaching international law, it "could and should be put beyond doubt" with changes to the Crimes Act, according to the watchdog's review.

"When you are looking at bail, you've got to look at the age of the child," Mr Moses said.

"If it is a child who is 10 or 11, one would think that is something the court should take into account as an exceptional circumstance."

'We should not be flouting our international obligations'

Mr Santow said judges needed to be able to weigh up all the circumstances.

"Sometimes it will be appropriate to detain a child pending their trial for a terrorism offence, even if the child is ultimately found not guilty," he said.

Mr Moses said terrorism laws were "not just about locking kids up". ( Supplied: New Chambers )

"But international human rights law requires special care to be taken, because detention can have such extreme effects on a child.

"If you're 12 or 15, or even 17, being detained can be the defining experience of your life, even if it's for a short time."

Mr Moses said it was "highly unlikely" the breach of international law could be used as a basis for appealing a conviction or sentence.

"What this should do, though, is alert the Federal Government to (the need to) amend the Crimes Act," he said.

"We should not be flouting our international obligations."

A spokesman for the Attorney-General said the Federal Government was considering the review and would respond in due course.