The European Union’s Court of Justice ruled December 21 that an attempt by United States airline operators to avoid inclusion in the EU’s Emissions Trading System is invalid and not justified by international law or specific agreements between the two parties. The judgment confirmed an earlier opinion of its advocate general, concluding that the EU has the right to permit a commercial activity in its territory only on condition that operators comply with EU criteria. The court rejected the argument from Airlines for America and a number of U.S. commercial airlines that the ETS could not apply to flights that mostly take place outside EU territory. Meanwhile, the China Air Transport Association suggested January 4 that Chinese airlines would not comply with the trading system, but officials from the European Commission have said that Chinese airlines have thus far complied with their ETS obligations. Airlines are required by March 31, 2013, to report on their 2012 emissions.