Contra la "prueba libre*

The traditional form (i.e. benthamian) of understanding the free proof has involved separating the notion of probability of evidentiary weight idea. This article states that the determination of the weight of evidence cannot be delivered to the preferences of the judge, but that the legal system must provide normative criteria that lead the judicial inferences. Evidence law should regulate de strategies of exclusion, preference and corroboration that guide the evidentiary inferences of the judges when uncertainty in order to minimize the risks of error and to distribute them among the litigants when they are unavoidable. To illustrate this argument, this article offers some examples of the criminal litigation.