Australia's asylum seeker processing centre on Nauru will face a legal challenge in the island's Supreme Court.
The case involves 10 asylum seekers who are facing rioting and wilful damage charges.
Australian barrister Jay Williams, who is representing the detainees, told a magistrates court on Wednesday he had been refused access to the centre by Australian Immigration Department.
He said he needed more resources to mount a proper defence as he was prevented from interviewing his clients, according to a statement from the Nauru government.
"The magistrate agreed that access refusal appeared to be in contravention of the defendants' constitutional rights and he would seek further information from the Supreme Court on the matter," the statement said.
AAP reports that if successful, the constitutional challenge by Mr Williams could have implications for the future of the centre.
The detainees had their bail extended until 17 June for the riot charges. Nauru's Supreme Court will hear the challenge on 7 June.
A spokeswoman for the immigration department rejected the claim by Mr Williams that he had been refused access to the detention centre.
"(The department) facilitated meetings between the lawyer and his clients off-site all day Tuesday 23 April and again on the morning of 24 April," a statement said.
"At no time, was the lawyer prevented from meeting his clients on this occasion - to the contrary, centre staff assisted and facilitated extensive meetings."
