The Balance of the Principle of Freedom of Obtaining Evidence with the Exclusionary Rule of Invalidity of Obtained Evidence through Illegal Means from the Point of View of Islamic Jurisprudence, Iranian law and Law of the West (With Emphasis on USA and Germany)

Discovery of the truth always is regarded as one of the most important issues of criminal trial which is feasible through obtaining evidence. Public security requires that the judicial authority does not hesitate to resort to any evidence to discover the truth, but what that is against principle of free obtaining of evidence are human rights guarantees. In other words, on the one hand there is the right to security that concerns the rights of the citizens, and on the other hand, the right to obtain that is related to the rights of the accused is arisen. Now, priority is assigned to which one of them? In this regard, the Exclusionary Rule and the Fruit of the Poisonous Tree Doctrine rule for the outflow of the evidence obtained through illegal means. The Exclusionary Rule deals with direct or firsthand evidence and the Doctrine addresses the indirect ones. Despite the origin of the Rule that is derived from the Common Law countries, in Islamic criminal law the principle is in favor of the validity of the evidence, unless the evidence is explicitly nullified or is obtained through illegitimate means. Absolute and strict implementation of this Rule throws the criminal justice system into crisis in discovering the truth. Accordingly, it is necessary to establish a minimum balance between the freedom of obtaining evidence and the Exclusionary Rule. In this regard, doctrines of status, independent source, deterministic discovery, weakening, goodwill and contemporary jurisprudential theory have guidelines that restraint the absolute implementation of the Exclusionary Rule.