There are multiple situations, often related to the administrative or judicial field, in which it is necessary to use a healthy skepticism, to question the validity of an assertion, appealing to the evidence that can prove or disprove it. (Shermer, 2008). From a child custody issue to facing a harsh criminal conviction, to applying for a disability pension or obtaining an indemnity in an insurance context; in all of them, there is the opportunity to use deception for one's own benefit, harming a third party, through fraud. As we know, opportunity, together with prior motivation or incentive and subsequent justification, constitute the classic fraud triangle proposed by Cressey (1961).
 This questioning of the validity of the case understood as its accuracy or correspondence with what it pretends to be and independently of its various types, is only possible from a method of analysis based on scientific evidence that benefits from using a system ordered by rules for the investigation - which we know as a protocol (Amezcua, 2000) - as well as a multiple approaches (Campbell and Fiske, 1959) that is proportionate to a conception of the detection and demonstration of deception from the approach of complexity (Cardozo, 2011). If, in addition, such a system was sufficiently flexible to be useful in the daily practice of the various fields in which it may be necessary to use it, it could represent a significant advance in this area.
 These, together with those of Behavior Analysis in Ethology, Criminology, and Psychology, are the initial theoretical bases on which the System of Analysis of Validity in Evaluation (SAVE) is designed, establishing four phases in two domains of multiple and orderly but flexible application, to scientifically question the validity of a case and provide it with consistency and even legal value when appropriate. Although SAVE was born in a clinical context (Domínguez-Muñoz et al., 2014) its main area of knowledge is the study of lying and deception, an area in which there is a large bibliography, somewhat dispersed among various disciplines, which must be incorporated as a source of academic knowledge for its use in the applied field (Domínguez-Muñoz et al., 2017).
 
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