Former military lawyer David McBride sentenced to almost six years ...

Former military lawyer David McBride has been sentenced to five years and eight months in jail for sharing classified military documents with journalists.

McBride pleaded guilty to three charges, including theft and sharing documents classified as secret, with members of the press.

ACT Supreme Court Justice David Mossop rejected McBride's case that he did not believe he was breaking the law, and found the offences were aggravated by his high security rating, which gave him access to the material.

He said McBride seemed to have become obsessed with the correctness of his own opinions.

But Justice Mossop did accept that McBride's mental health, which included PTSD, might have had a minor contribution to the offending.

The material released by McBride was used in the ABC's The Afghan Files story, which revealed allegations that Australian soldiers were involved in illegal killings.

McBride will serve a non-parole period of two years and three months.

David McBride arrived at the ACT Supreme Court this morning, accompanied by his assistance dog Jake.(AAP: Mick Tsikas)

Judge not convinced McBride was unaware of illegality of actions

McBride sat with his eyes closed and his support dog at his feet for the two-and-a-half hours it took Justice Mossop to hand the sentence down.

The public gallery exploded with shouts such as "shame on you!" and "you're a hero, David" after the term of imprisonment was outlined.

Afterwards, McBride hugged his ex-wife, who was crying, telling her "it'll be fine" before he was escorted from the courtroom.

In handing down the sentence, Justice Mossop read excerpts from McBride's interviews with Australian Federal Police officers, in which the former military lawyer said he believed it was his duty to expose illegal activity and that he always thought he would be vindicated at some point.

Justice Mossop told the court McBride's comments made to police were "vague and unparticular" and did not demonstrate his genuine belief that he was not committing an offence.

"I do not accept that he held a belief that what he was doing was not a criminal offence," he told the court.

He added that his preferred interpretation of the exchanges was that McBride had a desire to justify his conduct and expressed a hope that there might be a plausible legal defence for his actions.

'He decided he knew best'

Justice Mossop said deterrence was important in this case, taking particular aim at McBride's lack of remorse.

"The offender has shown no contrition for his offending," he said.

He said McBride chose to serve in the army but was not prepared to operate within the constraints of that organisation.

"He decided he knew best," Justice Mossop said.

"It's important to deter others from such conduct.

"They must know that breaching their legal obligations … will be met by significant punishment."

Justice Mossop added that this was especially critical when it had the potential to harm Australia's national security.

On the issue of rehabilitation, Justice Mossop said it was difficult to assess.

He said his prospects were "considered to be guarded because of his unwavering belief in his correctness".

McBride took hundreds of documents home in backpack, court hears

During a sentencing hearing earlier this month, the court heard 207 documents taken by McBride were classified as secret.

Prosecutors said McBride had copied the material, loaded it into a backpack and taken it home, over a long period of time.

The court was told the documents were stored in plastic bins in his cupboard, before being handed to journalists in a plastic bag for them to copy.

Justice Mossop described McBride's behaviour as "a gross breach of the trust proposed in him" as a legal officer in a sensitive position within the Australian Defence Force.

"That is clearly an aggravated feature of his offending," Justice Mossop said.

He said this was further emphasised by the fact McBride had received specific training about the handling of classified materials on a number of occasions throughout his military career.

McBride was charged after handing the classified material to journalists Andrew Clark, Chris Masters and Dan Oakes.

The court heard the journalists used it to publish stories revealing allegations Australian troops were involved in illegal killings in Afghanistan, even though that was at odds with McBride's intention in sharing the documents.

At the sentencing hearing, his lawyers argued his actions were honourable and that he believed there was "misconduct" occurring within the Australian Defence Force.

In a statement read to the court by his lawyer, McBride said he felt it was his duty to say something.

"I was looking for a crack investigative reporter, I couldn't do it myself," McBride said.

David McBride pleaded guilty last year to unlawfully sharing details of soldiers' alleged misconduct. 

'We have the funds to lodge an appeal'

Speaking outside court today after the sentencing, McBride's lawyer Mark Davis said they would appeal.

"We now, thanks to some recent social media activities ... we have the funds to lodge an appeal and we mean to do so," Mr Davis said.

"And the basis of that appeal is not so much today, it was the decision that his honour made some months ago when we changed our plea to guilty on the meaning of duty."

He said the legal team disagreed with a statement made by Justice Mossop previously, when he found McBride had no legal right or obligation to breach orders, and his actions were not justified by public interest.

"His honour ruled the duty of an Australian military officer effectively has one meaning, and that is to obey orders," he said.

"Well, we fundamentally disagree with that and we think it's an issue of national importance, indeed, international importance, that a western nation has such a narrow definition of duty."

He said McBride had acted in a way that was in keeping with "the oath that he made to his nation".

"We will be taking that as an appeal point and that's the only prospect of hope we can give to David today," he said.

Government 'wanted' prosecution: Wilkie

Independent MP Andrew Wilkie said the federal government "wanted to punish David McBride".(ABC News: Nick Haggarty)

In the wake of the sentencing, independent MP Andrew Wilkie criticised the federal government for not intervening in McBride's prosecution.

Mr Wilkie had been advocating for Attorney-General Mark Dreyfus to use his powers under the Judiciary Act to discontinue the prosecution, arguing it was "not in the public interest".

But Mr Dreyfus decided against this, saying the powers should only be used in "exceptional circumstances".

"The Attorney-General has chosen not to exercise his legal power to intervene in the David McBride case, and as a direct result of the federal government's inaction, the first person to front a court over war crimes in Afghanistan, the first person to go to jail over war crimes in Afghanistan, is the whistleblower," Mr Wilkie said.

"David McBride, the Afghanistan whistleblower, will be imprisoned for at least two years because that's what the government wanted.

"The government wanted to punish David McBride for causing trouble, the government wanted to punish David McBride to send a signal to other insiders to stay on the inside and to stay silent."

Greens senator David Shoebridge voiced similar outrage with the outcome, saying it would have a "chilling effect" on other whistleblowers.

"This is a shocking outcome that we've just seen happen with David McBride, facing … years behind bars for the crime of telling the truth," Mr Shoebridge said.

"A chill has spread across the public service, across the Defence Force, across anybody thinking about speaking up when they see wrongdoing, if they see a war crime, if they see abuse of public resources."

Attorney-General Mark Dreyfus said the prosecution of McBride was conducted independently of the federal government.

"The decision to prosecute David McBride, and the conduct of that prosecution, was the responsibility of the Commonwealth Director of Public Prosecutions," a spokesperson for the Attorney-General said.

"The CDPP is independent of the government of the day — a very important feature of our criminal justice system."