On Monday, the California Supreme Court declined the environmental impact report for the planned Newhall Ranch development. The court has declared that it understated the impact of the greenhouse gas emissions from the project and didn’t protect a dying out species of fish properly.

The ruling has come as a blow to the project, which was planned for the building of over 20,000 new homes, a commercial district and a number of schools on a nearly 2,500-acre parcel in Santa Clarita. The whole 12,000-acre project is mainly undeveloped open area.

The high court has ordered a lawsuit by the Center for Biological Diversity, wherein it has challenged the 2010 certification of an environmental impact report on the project by California Department of Fish and Wildlife. A Los Angeles County Superior Court had reversed the certification, however, later on the 2nd District Court of Appeal restored it.

As a result of the high court's ruling, there are no more appeal avenues for the case’ defendants, the California Department of Fish and Wildlife and the Newhall Land and Farming Company.

On Monday, each defendant released a statement. The Newhall Land and Farming Company said, “We are reviewing the decision of the Supreme Court and will continue to consult and work with the California Department of Fish and Wildlife on appropriate next steps consistent with the Court’s guidance”. It added that they were committed to realizing the vision of Newhall Ranch and the major advantages promised by it for the future and economy of Los Angeles County.