Various NGOs and individuals persuaded a panel of the Austrian Federal Administrative Court to overturn the government of Lower Austria’s approval of construction of a third runway at Vienna’s main airport. The reason: authorizing the runway would do more harm to the public interest than good, primarily because it would be contrary to Austria’s national and international obligations to mitigate the causes of climate change. Of the authorities cited by the court, the most important was Austria’s Climate Protection Act of 2011, which set emissions reduction targets for various sectors, including the transport sector. Because a third runway was expected to increase Austria’s annual CO2 emissions, the court concluded that it would be at odds with the provisions of the 2011 Act as well as with Austria’s constitution and its international commitments under EU law and the Paris Agreement.
The Austrian Constitutional Court overturned the Federal Administrative Court’s decision in June 2017, citing multiple errors that led the lower court to improperly give weight to climate change and land use considerations in the balancing test it used to consider the public’s interest in a third runway. The errors identified by the Constitutional Court included:
- misconstruing the Air Traffic Law’s instruction to consider environmental protection over-broadly by factoring in environmental impacts beyond those directly attributable to air traffic;
- wrongly including in emissions projections aircraft emissions attributable to flight segments other than landing and takeoff;
- improperly superimposing regional greenhouse gas emissions reduction targets on an analysis of legal rights and obligations under the federal Air Traffic Law; and
- misapplication of the Kyoto Protocol and Paris Agreement, which the Constitutional Court explained are the source of international obligations for Austria but are not generally applicable in the domestic legal context ("sie erzeugen daher nur eine völkerrechtliche Verpflichtung Österreichs und sind innerstaatlich nicht unmittelbar anwendbar").
In March 2018, the Administrative Court issued a new decision that approves construction of the third runway.