The 46 property owners of uninsured properties or vacant land, known as the Quake Outcasts, and developer Fowler Developments challenged the lawfulness of the Crown's offers, saying they weren't in accordance with the act and breached their human rights.
At the heart of the dispute was that insured property owners were offered 100 percent of the 2007 value, something not open to bare land owners which can't be insured, or the uninsured property owners who fell outside the net for various reasons.
The Human Rights Commission made a submission as an intervener, saying there wasn't a rational justification for the differential treatment.
While the insurance status of properties was relevant, the judges said there were a number of other factors that also should have been taken into account in determining whether there should have been differential treatment.
"The plight of those left behind in the red zones has thus been exacerbated by the actions of the Crown in making purchase offers to insured red zone property owners," the judgment said.
"The remaining individuals in the red zone have been effectively left in a dilapidated urban area that will worsen as it is further abandoned. This cannot enhance their recovery from the earthquakes."
The judges accepted the Quake Outcasts' submission that the red zoning decision was designed to encourage people to leave the area, even if they didn't use compulsory acquisition powers granted to the Crown under the Canterbury Earthquake Recovery Act.
"It is unrealistic to describe the transactions that occurred as voluntary," the judgment said.
"The inhabitants of the red zones had no realistic alternative but to leave, given the damage to infrastructure and the clear message from the government that new infrastructure would not be installed and that existing infrastructure may not be maintained and that compulsory powers of acquisition could be used."
By not using a recovery plan, the judges said the Crown's decisions "undermined the safeguards, community participation and reviews mandated by the act."
The judges declined to make a declaration on the unlawfulness of not using a recovery plan, saying it wouldn't serve any useful purpose.
Chief Justice Sian Elias and Justice William Young dissented, and both would have dismissed the appeal.
The Chief Justice considered it too much of a stretch to say that a recovery plan was needed and would have declined making the declaration, while Justice Young's view was that the order was lawfully made.
In a statement, Earthquake Recovery Minister Gerry Brownlee said Crown Law and the Canterbury Earthquake Recovery Authority are reviewing the decision and will assess what steps need to be taken in response to the ruling.