1) Scientific Evidence
The first question that requires a ruling of the United Sections regards the probative value of scientific evidence or circumstantial evidence, when it is in the presence of an investigation involving a high level of technical difficulty, but it was performed disregarding the recommendations of international human repertazione and interpretation data.
In this respect, it is necessary to assess whether this controversial figure, taken in violation of methods strongly recommended by the international scientific community (eg. Those issued by the International Society or no probative relief.
The profile in question assumes a crucial importance in the present case, since the contested judgment considered fully reliable and, therefore, conclusive conclusions reached by Dr. Patrizia Stefanoni (Scient Pol.) In order to trace DNA on the clasp Bra (rep. 165 B p. 240-250 and 320 sent. analysis results on the track 36B (blade of the kitchen knife), the Court held that the reference value they could take seriously circumstantial evidence (p. 321 sent. ).
In this regard, it should be pointed out that the expert report ordered on appeal, signed by Profs. Rather old and accounts, concerning the reliability of the results conducted by Dr. Stefanoni on these two findings (36 and 165 B), had led to a substantial unreliability of such assessments due to non-compliance with the procedures of inspection and repertazione, as well as for failure of international recommendations concerning the interpretation of the data.
However, the requirement of controllability marks the boundary between scientific and non-scientific theories; on the other hand, it is known that a scientific law can be considered as such only after being subjected to repeated attempts to overcome counterfeiting and after receiving repeated confirmations.
Other unfailing requirement is that of the widespread acceptance of the method within the international scientific community, because the failure to validate a specific technique means scientific uncertainty, which can not only achieve the acquittal of the accused when the evidence of guilt depends on it, given the uncertainty of the result.
For the above reasons, it is clear based on what parameters it may be considered that an investigation has technical validity of evidence or clue, or, conversely, when it is considered to be unreliable, that is unfit to compete, along with other elements, to base an assessment of responsibility.
The Court has held that "in assessing the results of an expert or technical advice, the judge must verify the scientific validity of the criteria and methods of investigation used, when they present themselves as new and experimental and therefore not subject to the scrutiny of a number of cases and the critical comparison between the experts of the industry, so they can not be considered yet acquired the assets of the scientific community "(Court of Cassation, Sec. II, July 11, 2012, Rv. 254344; Cass., Sec. II 17 October 2003, n. 834, Rv. 227854).