A legal bid to stop an Australian-born asylum seeker baby from being deported has reached the high court in a test case for Australia.

Ferouz was born in a Brisbane hospital in November after his mother, father and two siblings were transferred to Queensland from the Nauru detention centre. Last month the federal government rejected an application for a protection visa for Ferouz, and the child was classified as an unauthorised maritime arrival despite being born in Brisbane. The baby’s mother was pregnant with him when the family, who had left Indonesia by boat, arrived on Christmas Island.

On Friday, lawyers for the family filed documents in the high court challenging that decision. Lawyer Murray Watt said it is a test case on the legality of removing an Australian-born child for offshore processing.

“For the Department of Immigration and the Australian government to decide that a boy born in Brisbane’s Mater Hospital has come to Australia by boat is a new low when it comes to how the Australian government treats the children of asylum seekers,” he told reporters outside the court. “I think many Australians believe that Australia is a better country than that.

“It is simply ridiculous. This is an important test case that will potentially affect the rights of all babies born to asylum seekers in Australia.”

The family remains in detention in Brisbane.

Ferouz’s parents, from the minority Rohingya group in Myanmar (Burma), fled their homeland more than a decade ago. Watt said they lived for years in Malaysia and Indonesia in refugee camps before making their way to Christmas Island.