Some of the jurisprudential reasons which are discussed in the books of principles of jurisprudence are called practical principles (usul-e-'amaliya).. One of the practical principles is the principle of istishab(presuming continuation of the status quo ante).It may happen that those who must apply the justice, while setting disputes or applying civil or criminal statutes , would face with some cases that there are no express for them in the legal systems and codified laws. It is here that those who must apply the rules and judges , with the use of the nature of the laws, judicial precedence and legal doctrines and, in some cases , with respect to practical principles will on the base of them , resolve the problem in question.
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