Though having been accepted, the formal documents presented in Iran’s civil law, like a confession, testimony, and oath, feature limitations, especially now that they cannot be expected in the specialized, technical, and complicated issues to remain accountable to all aspects of a legal matter. In the lawsuits filed for demanding of loss compensation and in civil liability cases, the judges issue a writ of advisory opinion and refer the case to the experts of each specialized field for the recognition of the issue, calculation , and estimation of the guilt rate of each party (liable and loss-incurred). The experts investigate the case and determine the amount and percentage of each party’s fault. As for the nature of advisory opinion, there are discrepancies. A group of jurisprudents realize advisory opinion as being of a testimonial nature and believe that the testimony conditions, i.e. numerosity and justice, should be existent for the advisory notion to be valid whereas another group underlines its independent nature and finds certainty sufficient for the validity of the advisory notion. In the judicial procedure, the advisory notion is considered valid to the extent that the amount of compensation payable by the liable party is specified based thereon hence the expert’s idea can be enumerated amongst the other proofs of claim justification as an independent justificatory proof and it might be even considered superior thereto. The present study made use of an analytical-descriptive method to evaluate and analyze the nature and validity of the advisory note against the other proofs of claim justification.
