The Uses of Reasonableness in the Constitutional Interpretation and Arbitration: A Comparative and Theoretical Analysis about the Law in Action

This paper outline the main uses of reasonableness in the European constitutional practice, as well as in the international commercial arbitration, such as in the ICC and in others main European commercial chambers case law. It is important to deal with this subject matter as reasonableness is a very general concept that is routed in our common languages and may put in contact the western and the middle Eastern legal traditions. Reasonableness is, for instance, a pivotal concept of the Unidroit Principles (2010 edition, hereinafter in brief the ‘principles’), which Arabic version has been launched in 2014 at a conference held at the sultan Qaboos university of Muscat. As the law in action shows in many countries , this concept is a vehicle for the development of law and plays a great role in the dialogue between legislators and judges. In this perspective reasonableness may also support the process of huge reforms currently carried on in Kuwait, as the Kuwait development plan 2015-2020 worthy points out. Above all, especially a comparison with the intense communication among European courts, including the European court of human rights, may be very instructive for everyone. As the principles as the upper courts (civil supreme and constitutional courts) show, reasonableness is used as a general “standards of fair dealing” witch is related to justice, dignity and many others values. Moreover, the well-known “reasonable person” gure is applied to make prognoses about future events (e.g. impediments in performing or unpredicted harms) or, conversely, to evaluate uncertain past event, the reliance between the parties, etc. Reasonableness is also considered as a source of law and a criterion of legal validity. It is a device to ll gaps and adapt laws to changing in context. In addition, it plays a leading role in the legal interpretation as refereed to legislation, constitutions, customs and so forth. The pros and cons of this extensive use of reasonableness in the law are open to dispute. What is at issue is whether it represents a suitable solution of legal policy and legal drafting in order to develop legal certainty, equality and fairness especially in those case and transactions when the parties belong to differing legal system, legal traditions, cultures and languages. In this paper this issue will be examined in order to demonstrate that, in spite of a common view, reasonableness is not a notion embedded only in the western thinking and surreptitiously applied to impose certain values. Rather, history and philosophy, as well as the contemporary legal practice shows that, by means of reasonableness, everybody may give public reasons for justifying actions,choices,promises,etc.Asaconsequence,reasonableness is a device to solve legal issues by an argumentative practice based on reciprocity and mutual respect.