Inclusion of aviation in the European Union's emissions trading scheme is compatible with international law, concludes an initial opinion from a European Court of Justice advocate general.
Airlines will have to acquire and surrender emission allowances for flight to and from European airports once aviation is included in the scheme from 1 January 2012.
While the plan has caused a storm of protest among airline organisations, particularly from North America, the advocate general has put forward a legal opinion that the scheme is in line with relevant international agreements.
US and Canadian operators have claimed the European directive contravenes several international pacts including the Chicago Convention and the Kyoto Protocol, as well as the basic principles of law relating to sovereignty.
But advocate general Juliane Kokott's opinion said the inclusion of international aviation in the trading scheme is "not contrary" to international law.
"The principles of customary international law and international agreements relied on do not give rise to any legal objections, not even in so far as the EU emissions trading scheme extends to sections of flights that take place outside the airspace of member states of the EU," she said.
The directive does not contain any extraterritorial provision, she added, nor does it infringe the sovereign rights of third countries. Airports within the EU provide an "adequate territorial link" for the whole of a flight to be included in the emissions scheme.
"There isno impermissible unilateral action on the part of the EU outside of the framework of the ICAO since - under the Kyoto Protocol - the limitation and reduction of greenhouse gases is not the exclusive competence of the ICAO," said Kokott's opinion, which also added that the US-EU 'open skies' agreement did not rule out application of market-based measures on emissions either.
Inclusion of all flights to and from the EU, she pointed out, was compatible with the "principle of fair and equal opportunity" laid down in the 'open skies' pact.
"Indeed it is precisely that inclusion that establishes equality of opportunity in competition, as airlines holding the nationality of a third country would otherwise obtain an unjustified competitive advantage over their European competitors if the EU legislature had excluded them from the EU emissions trading scheme," she said.
Although the advocate general's opinion is not binding on the European Court of Justice, and a formal judgement will be issued at a later date, the advocate's role is to propose an independent legal solution to cases.