Manus Island detainees who missed out on a $70 million compensation settlement may benefit from a separate decision.
A class action, launched by Slater and Gordon three years ago, was settled by the Australian government and centre operators in June without any admission of liability.
Payments from Australia's largest human rights class action settlement were due to flow to 1698 detainees on Friday.
However many detainees missed out, but a decision of the full bench of the Papua New Guinea Supreme Court on Friday could help them.
The full bench ruled the human rights of all those sent to Manus Island had been breached.
"The application to enforce constitutional rights post Supreme Court decision (to close the Manus centre) is competent," the judgment read.
A further hearing is expected in February 2018, at which lawyers for the detainees will seek orders the Australian and PNG governments provide a safe, third country for the asylum seekers.
"The finding opens the way to a major compensation and also for consequential orders against both the PNG and Australian governments," Refugee Action Coalition spokesman Ian Rintoul told AAP.
"Asylum seekers who missed out on compensation from the Slater and Gordon case will be eligible for payment for the breaches of their human rights."
The Supreme Court has also set down a hearing in February to examine an application by Kurdish refugee Behrouz Boochani, relating to alleged human rights breaches involved in the eviction of detainees from the Manus detention centre at Lombrum.
