The Nauru government has deported its resident Magistrate Peter Law back to Australia.
The Department of Foreign Affairs and Trade (DFAT) confirmed Nauru had sent Mr Law home, but was unclear exactly why.
"We understand Magistrate Peter Law was deported from Nauru this afternoon. This is a matter for the Nauru government," a DFAT spokesperson said in a statement.
"The Australian government is seeking clarification of the facts surrounding the deportation."
Mr Law was due to hear the court case of the 152 asylum seekers charged over riots at the detention centre in July last year.
The riots left Australia's asylum seeker centre on Nauru in ruins.