The possibility for public administration to avail itself of contractual arbitration (arbitrato irrituale) is precluded, with consequent nullity of the relative arbitration clause having as its object matter not capable of arbitration, and consequent nullity of the award as being founded on a null arbitration clause.
The defect of potestas iudicandi of the arbitral tribunal, entailing an incurable defect of the award, may and must be raised of the court's own motion in challenge proceedings, even at the stage of legality review, with the sole limit of res judicata, independently of previous pleading in the arbitral phase, where it derives from the nullity of the arbitration agreement or arbitration clause.
In contractual arbitration (arbitrato irrituale), arbitrators are entrusted with the resolution of the dispute solely on a contractual basis, by means of an amicable composition referable to the will of the parties themselves, who undertake to consider the arbitral decision as an expression of their will.
Nullity may be raised of the court's own motion not only when an action for performance is brought, but also when an action for resolution, annulment or rescission is brought, under any aspect and even where a special or protective nullity may be configured.
The power of official notice of nullity of contract belongs also to the court seized of an appeal relating to a dispute having as its object a claim that presupposes the validity and efficacy of the contractual relationship that is the subject of allegation, this being a question pertaining to the constitutive facts of the claim and integrating an exception that may be raised of the court's own motion even on appeal pursuant to Article 345 of the Code of Civil Procedure.