Mathew Batsiua and Squire Jeremaiah, who were opposition MPs at the time of the protest, had their passports confiscated when charges were laid.
On 13 September Justice Geoffrey Muecke granted a permanent stay on the charges faced by what had been dubbed the Nauru 19.
Mr Batsiua said both men have since sought the return of their passports, which he believes should have been done within about 48 hours but this hasn't happened.
He says the government may be using section 18 of the Passport Act to justify with holding the travel documents.
