A popular case from the Greek law can help us to understand the legal effects derived from this phenomenon, and it would be useful as a reference precedent for any national court for ruling over a similar case. Twenty years ago, the Greek government celebrated a concession contract for building and operation the International Airport in the Capital with a contractors consortium. A series of articles in the contract set some conditions which are important for the phenomenon in question. In one of them (25.1.1), which referred the Article 26 of a National Law (2093 of 1992), it was established that the tax exemptions that benefited the consortium in the construction of the airport would had effects until the last day of last year. In another article (43.1), it was provided that any dispute would be submitted to an arbitral court, in case of the parties could not resolve it in accordance with another article (44.1), which talked about the resolution of the agreement. The arbitral tribunal would be the London Court of International Arbitration, and it would be composed by three arbitrators.
Five years ago, the Greek government imposed an additional VAT to the consortium, in relation to a tax audit that took place that year, the reasons behind this measure had to do with several transactions (and their respective fines) for incorrect value added tax declarations. So the company submitted a request against the Greek authorities to the London Court of International Arbitration for making effective the contractual disposition mentioned above. The tribunal issued an award two years later, and its decision stated that the Greek government had violated the national law and that such imposition was illegal, according to the article 26 of the 2093 of 1992 law.
The Supreme Court accepted the request and considered that, because both parties had agreed that the 26th article of the Greek Law about the tax treatment was part of the original contract, the decision of the London Arbitration Court was valid and did have jurisdiction for interpreting and applying the significant clauses of the concession agreement (even if it had no faculty for annulling an administrative act, because such power can only be held by local administrative tribunals). The Court respected the basic Law principle about contracts as Law for both parties. In consequence, the dispute had to be resolved according to the dispositions of the contract, because the contractual conditions were still active.
The interesting features of this international private law case is the fact that a foreign tribunal have interpretative faculties over a national law. The case is an example about arbitral courts with jurisdiction for deciding on national matters, and its essential condition: when both parties establish in the contract clauses that controversies will be resolved in an arbitration tribunal. It is not enough to state in the contractual conditions that the effects of a specific article refers to a national law: the direct consent of both parties for submitting any dispute to an arbitration tribunal is needed.