A New Zealander with no criminal convictions, now being held in detention in Australia, was one of the soldiers in Prime Minister John Key's protection team during a visit to Afghanistan.
Former Lance Corporal Ko Haapu's visa has been cancelled by the Australian government under tough new rules that have seen dozens of convicted criminals detained and deported.
Mr Haapu's visa was cancelled on character grounds - as set out in Section 501 of the Australian Migration Act - because he was a member of the Rebels Motorcycle Club.
He is currently being held in a Perth prison, despite having no criminal convictions in Australia or New Zealand.
His lawyer Michael Pena-Rees said the decorated ex-soldier should be released immediately.
"He's put his life on the line for the people of New Zealand and his fellow soldiers."
Mr Haapu's partner Teresa Mariner said the way he was being treated was disgusting.
"I'm absolutely devastated and shocked. It's a real kick in the teeth, to be honest."
She said he was visiting one of his friends in prison and, as they were leaving, police surrounded the car and pointed a taser at him, dragged him out of the car and threw him on the ground, before taking him in and holding him in solitary confinement for six days.
Mr Key said today he remembered Mr Haapu's face from the team that accompanied him in Kabul, and when he travelled to Bamyan.
He did not have the particular details of his case, he said.
"Because the Australians won't give that to us, but you will have seen the statement made by the Australian Immigration Minister who has said that, yes, obviously there's a character issue in terms of association with an outlawed motorcycle gang.
"But there seems to be also other information that the Australians have that the minister's pointed to - I don't know what information the minister has."
Mr Key was asked whether he had contacted the Australian authorities about this particular case.
"Not specifically in relation to him, I don't deal with individual cases.
"I mean, all we can is deal with the situation as it presents itself. We can't stop the Australians doing what they do - they have a sovereign right to do that.
"We may not agree with it, we've advocated very strongly... but in the end, it is what it is."
Mr Key said it was not a matter of him being unwilling to step in to help.
"I don't know all of the particular facts - all we can do is do all the things we have done."
Visa cancellation on character grounds 'challenging'
Mr Key said the policy of cancelling visas on character grounds was one of the provisions in Australian migration law to which the New Zealand government strongly objected.
"Because it has a subjective nature, and most New Zealanders would say someone that's been convicted of a serious crime - they could probably understand why that person might lose the right to live in another country.
"If it's basically solely on the kind of character that you are and the associations that you have, people would find that a lot more challenging, I certainly do."