Contractual arbitration (arbitrato irrituale) arises where the parties confer upon the arbitral tribunal a binding decision-making function, encompassing the assessment of both the quantum and the an debeatur, as may be inferred from the formulation of the mandate and the common intention of the principals, to be ascertained also on the basis of the overall conduct of the parties, including conduct subsequent to the conclusion of the contract, pursuant to Article 1362 of the Civil Code.
The characterisation of the subject matter of the dispute referred to the arbitrators constitutes a question of interpretation of the principals’ intention and amounts to a finding of fact reserved to the trial judge, not reviewable on appeal if conducted in compliance with the criteria of contractual interpretation and properly reasoned.
A contractual arbitration award (lodo arbitrale irrituale) may be challenged for essential mistake, pursuant to Articles 1427, 1428, 1429 and 1431 of the Civil Code, where the formation of the arbitrators’ will has been distorted by an altered perception or a false representation of reality and of the factual elements submitted to their examination, such as to have had a decisive influence on the decision.