A fundamental question at the beginning of any arbitration is whether any public policy rules prohibit the dispute to be decided by arbitration. As arbitration became a widely accepted alterna- tive to litigation in national courts, the scope of arbitrable disputes was expanded to allow for a wide range of disputes to be resolved through arbitration. The authority to restrict arbitrability lies with the legislator, which generally does so only in cases where it is war- ranted by serious public policy concerns. The Slovenian Arbitration Act is a modern act that provides for a wide concept of arbitrabil- ity. When the Slovenian legislator unexpectedly tried to restrict the arbitrability of concession disputes by adopting an authentic inter- pretation of law restricting arbitrability for concession disputes, it created significant uncertainty for the parties who have included an arbitration clause in their concession contracts or who were consid- ering doing so. The Slovenian Constitutional Court confirmed that the authentic interpretation of law cannot be used to give binding interpretations on how to rule in specific cases because it would undermine the core principle of the separation of powers and inde- pendence of judges. While it has now been settled that the authentic interpretation should not be applied, it nevertheless remains a skel- eton in the legislator’s closet since the legislator had not expressly invalidated or retracted the authentic interpretation.Osnovno pitanje na početku svakog arbitražnog postupka je to da li pravila javne politike onemogućavaju rešavanje spora putem arbi- traže. Budući da je arbitraža postala široko prihvaćena alternativa parnicama u nacionalnim sudovima, krug arbitražnih je sporova proširen, što je omogućilo širok dijapazon sporova koji se rešavaju putem arbitraže. Ovlašćenje ograničavanje arbitrabilnosti leži na zakonodavcu, koji obično to čini samo u slučajevima kada je to opravdano razlozima javne politike. Slovenački Zakon o arbitraži predstavlja moderan propis koji predviđa široko definisan kon- cept arbitrabilnosti. Kada je slovenački zakonodavac, usvajanjem autentičnog tumačenja zakona, neočekivano pokušao da ograniči arbitrabilnost koncesionih sporova, javila se neizvesnost za stranke koje su prethodno u ugovorima o koncesiji ugovarale arbitražne kla- uzule. Slovenački Ustavni sud potvrdio je da autentično tumačenje zakona ne može da se primenjuje kao obavezujuće u presuđivanju u konkretnim slučajevima, jer bi to potkopalo osnovni princip podele vlasti i sudske nezavisnosti. Premda se stalo na stanovište da auten- tično tumačenje ne treba primenjivati, ono ipak još uvek postoji, imajući u vidu da ga zakonodavac nije izričito poništio ili povukao
