linguistic:paraphrasing
Arbitrator advocates

In some legal systems, it used to be common for each party to the dispute to appoint an arbitrator and for those two arbitrators to appoint a third arbitrator (who may or may not be called an umpire). However, the two arbitrators appointed by the parties to the dispute would essentially act as advocates for the party who appointed them, and the umpire would effectively act as a sole arbitrator. Such systems can lead to difficulty, as other countries may be reluctant to enforce an arbitration award where two of the three "arbitrators" are clearly unable to demonstrate impartiality or independence. The standards for enforcing such awards are set out in the New York Convention, as interpreted by local law.