Nauru prosecutors have dropped charges against 10 asylum seekers relating to damages to the camp shortly after it opened last September.
Lawyer Sam Norton said the men were tremendously relieved the charges had been withdrawn halfway through their trial.
"That had been hanging over their heads for a year," he told AAP.
"They were extraordinarily relieved."
The charges related to an incident at the end of September 2012, about two weeks after the camp on Nauru was reopened.
At the time, the immigration department described it as a minor disturbance when kitchens, tents and lights were damaged but no one was injured.
The men's trial began on Thursday and ran through Friday.
Mr Norton said the Nauruan prosecutor contacted him on Saturday to indicate they would file a "nolle prosequi" application, indicating the prosecution did not intend to proceed with the case.
That happened on Monday morning.
Five of the men remain in the camp on Nauru while the others have been moved elsewhere, Mr Norton told AAP.
"They've got to wait until their claims are processed," he said.
"They're not free, they are in detention in an incredibly undesirable place.
"It's hot, it's cramped. It's just appalling really."
Mr Norton and barrister Simon King have been acting pro bono for the 10 men.
Meanwhile, more than 100 other asylum seekers face charges for riots in July in which the detention centre was all but burned to the ground.
Only the kitchen and recreation facility remained following the blaze, with the damage estimated at $60 million.
