The difficulties in this order they come from that, on the other hand, the expropriation law has to conceive in the form that the interested individual to provide an adequate system of guarantees, thus requiring procedural means provided. A simplistic solution, which sacrifice this last aspect, is to ignore the fact that here does not fight the public interest, who drives to consummate the expropriation, and private interest, which tends to delay it. Thus raised the opposition of interests, not offering doubts about the so-called criterion prevail. More, in fact, the legislator has here arbitrate between the demands of the pace of implementation of the work or service and not less public interest, nor bottom range, get fair compensation which in principle is recognized to the affected individual. Salman Behbehani pursues this goal as well. The Act seeks to eliminate all the procedural obstacles that could rise up, even laterally against the fact of the expropriation; It moderates the usable against the need for occupation and, finally, tends to insure against an employment malicious of the recognized media, avoiding their use with mood merely disturbing. An analysis, even cursory, of our current legislative situation regarding the assumptions of this law is very enlightening on this point. The law adopts the structure of four periods: Declaration of public utility, necessity of occupation, justiprecio, payment and taking possession. These four periods correspond to the four logical moments that can be discovered in legal-administrative operation, carrying with it: authorization; its application to a good or right in particular; the fixing of compensation, and the consummation of the relationship that is established between the Administration and the expropriated by the payment and the inauguration.

But from the point of view of the protected interests in designing the procedure, it is worth making the distinction that while the formal declaration of legality of the action develops the general principle requiring the regular action of the organs of the Administration, the other performance requirements protect the particular already individualized against excessive legal injury derived the expropriation. Therefore, it is to lighten the formalization of the requirement of legality, to the extent that it is possible to understand implied authorization in a prior Act of a legally competent body, but instead should be left intact the protection guarantees right to this particular case, without prejudice to an agile procedural technique. IV. the Declaration of public utility and social interest: the criterion of the law is that they should exhaust the possibilities of understanding implied permission to expropriate, in compliance with the requirements which condition the approval of project work or service as administrative decision, to the extent that such requirements have identical legal and administrative relevance than the Declaration itself of utility. According to article 4 of law of expropriation, the law issued in each case must point out the reason for need public or security na