Full coverage: The South China Sea Issue

Chinese Foreign Minister Wang Yi has called the arbitration "a political farce under the pretext of law." And Vice Foreign Minister Liu Zhenmin has questioned the credibility of the arbitrators.

The Arbitration Tribunal, established in June 2013, consists of five people. They are Rüdiger Wolfrum from Germany, Thomas A. Mensah from Ghana, Jean-Pierre Cot from France, Stanislaw Pawlak from Poland, and Alfred H.A. Soons of the Netherlands. None of them are from Asia.

The German arbitrator was elected by the Philippines. China did not elect anyone as it stuck by its position of not participating in or accepting the arbitration.

What stands out is who appointed the other four on the panel. That decision maker was Shunji Yanai, a former Japanese diplomat. He was President of the International Tribunal for the Law of the Sea from 2011 to 2014.

The right-wing former politician helped Prime Minister Shinzo Abe lift the ban on collective self-defense right. And he takes an anti-China stance.

Yanai once claimed on a TV show of Japanese broadcaster NHK in 2013 that Japan should build up its military might against its "threat and enemy".

"From the very beginning of this case, from the appointment of its presiding arbitrators to the composition of the members, manipulation was easy," said Gong Yingchun, assoc. professor of China Foregin Affairs University.   

"Rules were specially made for this case, different from the rules of the International Tribunal for the Law of the Sea and other courts that are set. There was little restraint on the rules. But the case it handled is far from simple."